on scratch paper, make a grid for all the questions across and A through E going down.
follow the strategies in kaplan and on this site. basically read the question and decide if it looks right.
1. if it doesn't - read the other choices(B,C,D,E as A is always the original). Generally, they are testing one or possible two areas. Read the other choices and scan for the differences. This will tell you what they are looking to catch you on. there's usually a 2/3 split among the choices, meaning that 2 of the sentences will be written one way and 3 will be written another. one of these ways has to be wrong. eliminate the ones that are wrong. among the remaining there will be subtle differences decide amongst these, crossing off the ones that are easily incorrect
2. if it does - read the other choices (B,C,D,E) anyways. you may have missed something and looking at the others should clue you into what they were testing and you can decide whether you're right or not.