Still an undergraduate, a third-year math student. Wanted to share some personal tips for the GMAT:
I used these few strategies after my first test.
1. Do not be ignorant. If you don't any topic, spend more time on it. By assuming that you will be able to solve a question on that topic on the exam will surely not help.
2. Practice as many questions from
the official guide as you can (especially quant). A lot of quant questions on my first GMAT were straight from
the Official Guide, but with different numbers.
3. Meditate for 10-15 minutes every day. Keeps you focused and prevents you from getting frustrated during the exam.
4. Sleep properly before your exam (minimum 8 hours, not kidding).
GMATPrep1 (Feb 05): 660 (Q:47, V:34)
GMATPrep2 (Feb 12): 640 (Q:48, V:31)
Kaplan free test (March 08): 710 (Q:49, V:39)
GMATPrep3 (EXAM PACK) (March 27): 690 (Q:47, V:38)
GMATPrep4 (April 2): 710 (Q:48, V:38)
GMAT (April 6): 640 (Q:50, V:27)
Started studying again on May 15
GMATPrep5 (May 30): 700 (Q:49, V:35)
GMATPrep6 (June 12): 690 (Q:50, V:34)
GMAT2 (June 17): 710 (Q:49, V:37)