I will suggest you to take a break of 1-2 weeks and go out ona nice vacation. Forget everything and come back fresh and start again!
Am not so good in Verbal so I might not be able to help you much in that. But I will share my thoughts anyways
I will suggest you to try
SC: Thursdays with Ron! Trust me it will help you a LOT! (SC score will go up buy 3-4 points for sure!)
CR: Powerscore CR
bible! (Take myw ord you can solve any question after reading thsi book! It wont take more than 3 days to finish this with confidence!)
RC: am not very good at this either. But do watch "Main idea" questions suessions by Ron in the Thursdays with Ron series! (You will get that questions right without fail with a 100% accuracy!)
The places where you will probably be screwing up are
1. The timing
2. The one odd tough question which you get once you do 3-4 questions correct in a row
3. First 10 and Last 10 questions.(as they have more wieghtage then the remaining questions!)
Now, how to improve:
1. When you solve a question and you have already taken 2mins and you don't see yourself going anywhere in that question in next 1min. Then guess and move on! (its not necessary to get all questions correct to get a 50 or 51!)
2. Identify the weak areas (which i guess you have) and try the following:
Prepare a xls sheet (topic by topic).. and keep a track of your progress on a daily basis. Use color coding (Red,Orange,Green).
Red: You are weak in theory - brush up your concepts.
Orange - Done with theory but weak in application of the concepts
Green - Done with the topic
3. Regarding the individual topics:
For i=1 to end
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.
4. Why grockit?
Because they have a timer for each and every question so it will help you improve your speed.
They have tricky questions which is what GMAT asks you!
5. General Advice
GMAT Quant is not tough - its tricky
Keep an eye on that then i guess you can help yourself out a bit.
Also, i read it somewhere that when you are doing good in Quant then you get either a probability or a PnC question. So if you get a question like that then its a plus for you!
6. Go to gmatclub and follow the discussions of the topics in which you are weak. Try to do the 700 level questions and try to follow the discussion which they have. It will help you in knowing how to think about the problem.
Good Luck for your prep!
Hope it helps!