From 580 (diag) to 680 (Q47 V35) to 710(Q49 V38

Overview

Objective:
I am sharing this experience to help other people that want to self-prepare for the GMAT. During this time, I learned a lot about myself and the GMAT and I think that by sharing this experience, people will learn from my mistakes and learnings, making their study easier. I know that it can get long, but if you want, below you will have a quick summary of my recommendations in the end of the post. Also, I want to thank some people that made my study easier by sharing high-quality material for free.

Background:
I'm from South America. I am an Industrial Engineer from a top engineering university and I consider myself a quantitative person. I speak good English and I read a lot in English, meaning that I had a decent/good reading comprehension. However, I NEVER learned a lot of grammar, therefore SC was a tough part for me. In high school my English was bad, but I kept watching videos, reading and communicating in English (my girlfriend is Chinese and we speak English) so I learned the language by practicing.
From the start, I knew I was going to self-prep for GMAT. My financial situation is not very good and I also felt that I needed to prove myself. My undergrad GPA was not very good and sometimes I felt I was not capable of achieving high goals. In other words, sometimes I felt stupid and I wanted to prove me wrong.

Personal Goal:
Goal: Because my undergrad GPA is low (6.5/10), I wanted to get something above 700. My dream schools were HEC (MSc in Strategy) and ESSEC (Adv master in Strategy and Management of International Business).

Diagnostic
At first, I honestly did not know much about GMAT, I knew nobody that had given the exam. After researching a bit about the exam, I thought that Quant should be my strong part and that Verbal should be my low point. I took my first diagnostic test and it did not go very well. I got a 580 (Q42 V28), meaning that I was not as good as I thought in Quant. I still had a lot of work to do in both sections.

Starting the self-prep
This was the hardest part for me. I think I was extremely lucky to find this forum. After seeing some study guides and experiences, I decided to spend about a month preparing for the quant section, 2 weeks for the Verbal section and the last 2 weeks preparing for both and doing CATs. I made a ton of mistakes during those 2 months, I wasted a lot of time studying useless things and I had the wrong approach.

Quant
For this section, I did not understand what topics to study. Therefore, I followed the ALL YOU NEED FOR QUANT thread. Something that I did not know that would have been very useful to know is this thread: Overview of GMAT math question types and patterns on the GMAT . This thread can easily summarize the topics that you need to focus on. Logically, you would want to focus first on the topics that appear more frequently.
After understanding which were the most important topics, I tried to do exercises. The best way that I found is to focus on one topic at a time. If I kept changing topics often, I feel like I kept making the same mistakes and I did not learn appropriately. This is when I realized that I would not have a good time with GMAT. I sucked at basic arithmetic. Even though I am an engineer, I am too used to the calculator, this was very bad for me. In middle-school and high-school I was a pretty bad student, so I struggled quite a bit in easy math.
Also, I would recommend trying to avoid official questions early in your practice since they are a scarce resource, it sucks to exhaust them early (another error that I made). After practicing, I made another mistake: I did not have a proper error log. This is a very bad mistake because you cannot track your strengths and weaknesses. Even though you have a rough estimation, you don’t know exactly the weaknesses. In the long term, I think this can have two effects: You miss the topics in which you should focus and you will lose motivation. The second one is very important, raising the accuracy of one topic by 10% is a good improvement, but probably you will find it hard to realize if you don’t have a proper error log.
When practicing, try to focus on quality over quantity. It's easy to say: “damn I missed this one because of X, but otherwise I would have been right”. If you make a mistake, analyze it. If it was a dumb mistake, take some minutes to relax and clear your mind so that you don’t keep making them.
To estimate my scores and relative strength in the topic I used two estimators. First, I found that the GMAT timer is a good estimator of one's score, at least on quant (I will go to that in the verbal part). Second, I adapted the GMAT Club error log to my own excel. This was very beneficial because I could have deeper insights, graphs, etc and it was easy to do (once a day I downloaded the data from GMAT Club error log and I uploaded it to my excel). If someone wants to know more about my Error Log, you can leave comments and maybe I can upload it or PM me.

Verbal
Surprisingly, I was not too bad on Verbal. Critical reasoning was my strong point, very strong. I did not know what a hypothesis, assumption, etc was but I still managed to reason my way out of hard questions. I practiced a bit here but I did not put a lot of focus on this topic. Sadly I do not have a lot of insights here because it was easy-ish for me.
Reading comprehension was okay, not too good but now awful. I tried to practice one or two passages a day to keep improving. I had good accuracy but not great (about 70% overall). I did not focus too much here on my prep. Reading comprehension is a relatively straightforward topic. First, get some good vocabulary, you can't understand a paragraph if you don’t understand the words individually. Second, don’t look for any shortcuts, they don’t exist. Read the passage carefully (but not too much) and try to understand the big picture. Finally, ask yourself Why? Why is this here? Why did the author include this?. This will help you understand the big picture and you will see your accuracy increase.
Sentence correction was my main weakness, I was horrible at it. At first, I couldn’t even solve easy questions methodically. I made a HUGE mistake here. I don’t know why I thought that by doing questions and seeing the answers I would learn it. Please don’t do this, there is a lot of excellent material to study sentence correction. If I had to retake the GMAT, the first thing I would do for sentence correction would be to watch GMAT Ninja verbal Wednesday. Great material, excellent explanations and honestly I felt it's all you need for sentence correction.
My biggest recommendation is to try to make the most out of the official questions. In the quant part, prep companies can make good questions to practice and to learn concepts, but in Verbal, there is nothing like an official question. Use them wisely and make the most out of them. If you got one wrong I would recommend you not read the answer and try it again in the future (again, an error log is a must).
I found that the GMAT estimator worked pretty well here too. Both of my scores were properly estimated. However, the estimator does not take into account the Reading comprehension questions. Therefore, the estimator reflects your CR and SC skills.

First exam
On the test day, I felt confident. Not because of my skills but because I felt that I did all that I could. I got some good 8 hours of sleep and I went to my test center. Big mistake, try to arrive very early, I arrived almost 10 minutes late (I had to run for the test center) and this made me pretty stressed. Maybe that influenced my score, but there is no way to know. I was hoping for a 700. When I saw the 680 (Q47 V35) I was disappointed. I felt that the Q47 was not good enough for top business schools (especially with an engineering background). The day after I had a trip to China for 10 days, I cleared my mind and decided to retake my exam. Coronavirus was starting in China so those were not the best holidays but I can't complain.

Second Self-prep
I bought the Enhanced Score Report, which gave me great insights on what I needed to improve. I would highly recommend it if one plans to take the exam again.
In quant my geometry was awful (I missed ALL the questions). Surprisingly my data sufficiency was good (49) but my problem solving was bad (47).
The verbal section went a bit better than expected, with a 40 in CR, a 35 in RC and 33 in SC. I was surprised that I got a decent score in SC.
I had a bit less than a month to prepare this time. I did not change my approach. I did exactly what I did for the first time but I learned from my mistakes. I improved my Quant by working specifically on the topics that I struggled with and that were often tested in the exams. I practiced a lot and reviewed my exercises. This made a huge difference and I started to be more consistent.
In verbal, I focused on improving my SC, watching GMATNinja’s videos was extremely useful. I could not have done my improvement if it wasn’t for this guy. I focused a bit to improve my CR and RC a bit but not a lot. For me, his clear explanations made SC way easier.

Second exam
I was a bit nervous this time, I don’t know why. Coronavirus was starting to hit France, so I guess that didn’t help. Luckily I was allowed to keep my mask during the exam, but it was uncomfortable. During the exam, I didn’t feel that I was doing good. I thought that somehow I was going to **** it up. But I tried to keep my head as clear as possible. When the score flashed, I was happy. It was the score that I was expecting. I was so happy and I accepted them so happy that I didn’t even check my IR score (who cares about that anyway right?).

Summary of recommendations
- Understand your starting point and your desired score. Be realistic and align your studying hours per week and the total duration of the preparation. I wouldn’t recommend studying for more than 3-4 months straight because you can get burned. If your gap is too big and your work schedule does not allow you to study a lot per week, maybe you can take a week or two off in the middle. Sometimes your brain just needs time to understand things.
- Focus on important topics. Topics such as Algebra, Arithmetic, and Geometry should be your first focus, other advanced topics will not be very good. Try to work using the Pareto logic, focus on doing 20% of the work that gives 80% of the results. If you are at a Q40 there is no need to learn advanced topics.
- It's better to do fewer questions thinking than just slide through questions saying “if I knew this I would have been correct”. Focus on quality over quantity and you will see huge improvements.
- Use an appropriate error log. You can’t make huge improvements without it. And even if you can, they will take longer.
- Even if you got a correct answer, have a quick look at the answers posted in the forum, you might learn some new approach. (or maybe you were just lucky and got it right for no correct reasons).
- Don’t exhaust the official questions if you are far from your desired score. Once you are between 20-40 points from your desired score, you can use them.
- GMAT is not a race, it’s a marathon, this means that it will take time. Find a good balance, don’t burn yourself studying but don’t be lazy.
- Keep a healthy lifestyle. This might sound obvious, but regular exercise, good sleep, healthy eating, and social life can help you tremendously.

Conclusions
My GMAT self-prep experience was a hell of a ride. I doubted myself several times. I was stressed, anxious and depressed sometimes. It was tough and it required a lot of hard work and discipline. However, now I can say that GMAT is a good exam. It really changes your way of thinking and I believe that you can learn something useful (even if you think that those annoying questions are useless). Furthermore, you can learn a lot about you, and this can be very valuable.
I want to say that I couldn’t have done this without the help of other people. I have named some users here that made excellent resources that helped me a lot. Bunuel, GMATNinja are just a few of them but there are a lot of folks that create guides, share experiences and reply to questions. Most importantly, I wanted to thank my girlfriend for the unconditional support that she gave me, this would have been way harder if it wasn’t for her. She supported me when I was a pain in the ass, when I was stressed, unhappy and a lot of feelings that GMAT test-takers will feel related to.
I believe that GMAT Club is an excellent tool and if you are self-preparing, you really should learn how to make the most out of this platform.

I wish all the luck to everyone who decides to take the GMAT and especially to those who will self-prepare. And thank you very much if you read until this point.