Many people have told you tips/techniques, but the few points I would emphasize are -
1) Do not stress about comb/permutations (I got only one of these types), but instead know number properties, exponents, etc. COLD. Those questions are much more common.
2) Don't get caught up in the first few questions - every single question is equally important, and guessing on the last few (Esp. if you see that the ones at the end you could have solved given the time) will piss you off more than not solving the one you probably couldnt solve anyway (And spent more than 2 minutes trying to figure out).
3) Here is the time tracking method I used (worked for me) -Every 8 questions, subtract 15 minutes from the clock. So at question 8 you should have ~60 minutes left, at 16 questions, have ~45 minutes left, etc. If you roughly track to this for both sections, you should be good.
4)Verbal - really important on readin comp to be aware of (and cross out) points that are too extreme (words such as always, definitely, etc.). In critical reasoning - watch out for scope creep. Sentence correction - as many others have said, study Manhattan SC and you will be fine.
In sum, I think the overall test comes down to how well you perform under pressure. I get nervous and am not a good test taker. I was literally shaking the entire test (and I didnt even have caffeine!).
My overall suggestions would be go in knowing that you are going to do your DAMN best, and the rest is history. Also, when working on each section, dont think about the one before or after, just the one you are working on. Use your breaks to get this through to your head when it doesnt want to cooperate.
Lastly, for study material I used -
OG 11
OG Quant
OG Verbal
Manhattan GMAT guides for Quant and SC
Good luck to all! =)
