This will be very general question, try to post a RC passage and pick up 3 questions and discuss your approach, how you try to approach the problem.
A few quick pointers are
1) use a pen and paper. After you read a para or a few lines. Summarize your reading in 5 words.
2) It would helpful to evaulate the what kind of questions you are getting wrong.
3) You should read the Manhattan RC guide book. it is very helpful.