RC
Start reading more!
Strategy1
Create a passage map as you read.
- Write a brief note about each paragraph as you read the passage
- Write down the point of view of the author (postive, negative)
- Write a heading for the passage
- Keep an eye on the places where details are mentioned. (so that you can easily refer back as and when required)
Answering the Questions:
1. Read the first question
2. Write down a prediction.
3. Use the passage map to locate the part of the passage. Eliminate the 3 out of scope choices.
4. Select the correct answer by re-reading the part of the passage which is discussed if you are not sure about the answer.
Good Book to practice passage map: RC99
Strategy2
As in the real exam you might not get the proper time to write the passage map and stuff then I will suggest you to read the passage first and then answer the questions.
General Advice
Start reading more of
https://www.smithsonianmag.com/https://www.scientificamerican.com/https://www.economist.com/And anything related to history and things which you don't like reading! (as am engineer so I don't like reading medical stuff)
Resource: Thursdays with Ron(you can find the link in my signature) is a good resource for RC. Specially for the "main idea questions"
CR
Did you try powerscore CR bible? Am not sure if this is the right time to change the book but if you can then its a good book!
Also, start practicing from grockit.com
SC
Try Thursdays with Ron (you can find the link in my signature)
Quant
Start working on the topics in which you are not that good
For i=1 to end
-> Study "chapter i"
-> go to grockit.com and schedule game for "chapter i" with difficulty level easy, If doing good then increase the difficulty to "medium" else go to next step
-> re-read the "chapter i" if you are doing bad
-> else goto next chapter and repeat the above steps.
-> practice a LOT on grockit.com!
Also, Start practicing questions from gmatclub. You can find the link to questions(sorted tag wise) in my signature
Good Luck for your prep!
Hope it helps!