Well !! First things first. Increasing your point from 480 will take some dedicated efforts but it is possible to increase this score to a 550 and also 600.
The best thing is you have a clear idea of what you want and how you can achieve it.
1) If you have a solid base and your basics are clear, it becomes very easy to increase the score from a 480 to 550. For basics, you can go through the GMAT Club (as you have less time). Check out the following:
a) All you need for quant (it has some valuable information)
b) Bunuel's posts
c) GMAT study plan for verbal by souvik101990
There are many other useful posts by GMAT club users that would help you.
2) After understanding the basics for example you studied numbers today, solve
official guide (number properties questions and ANALYZE every single step given in
the official guide). In addition, search for that question on this forum and see the different ways in which GMAT club users have answered the same question. FIND YOUR WAY AFTER GOING THROUGH ALL THIS.
3) Very important: No matter you get a question right or wrong, see explanations for every question.
Benefits of doing so:
a) For the questions you got correct, you can see and analyze if your way was the quickest way or not as you have on an average 2 minutes to solve a question.
b) For the questions you got wrong, you have to understand that what is it that you missed. For example, was it a basics problem or you did not understand the question as to what it was trying to ask.
See the basics are same (2+2=4) but in a 500 level question, the question asked would be direct and in a tougher question the language would be indirect.
4) You can make an
error log or use google doc to maintain your performance and practice the questions you got wrong every weekend.
5) Don't rush to solving 50 or 100 questions. Even if you solve just 10 or 20, you should be confident on what you just solved (the basics, the language, etc.).
6) You can watch some webinars conducted by
e-gmat (
e-gmat because I loved their webinars). IMPORTANT: They are free!!
7) Just know your strengths and weaknesses. Keep practicing and revising.
In the end, NO ONE KNOWS YOU BETTER THAN YOU AND THUS NO ONE CAN DEVISE A STRATEGY FOR YOU BUT YOU. So Good luck.
(You can also go through some debriefs on this forum)