My 2 cents:
1. Focus on solving instead of eliminating; but don't hesitate to switch to plan B (elimination). Key to elimination is: use the results from your solutions. For instance, you get very long word problem - write equations, etc and try to solve, but say you exceed 2.5mins, spend next 30sec (max 45 sec) to see what answers could fit your solution so-far.
2. Something most students don't realize until the damage is done. When you write an equation, make sure to choose right variable name.
Note: z-2, i-l-1,a-q-9, s-5,o-0, etc look the same. And during time pressure, many make mistakes while solving. I hope you get where I am going. Use Capital letters if you find it comfortable. I don't have this problem, as I write very clearly and am very aware, but I know this could lead to many silly mistakes for most.
3. DS question: read I and II, ONLY when you fully comprehend/reduce the stimulus (same as CR