Practice, practice practice. Get as many reading comprehension type examinations that you can find. Beyond the various MCAT prep books (AAMC, Flowers, Kaplan, Princeton, Columbia, Berkeley, REA, Peterson's, Examkrackers, ARCO, etc. -- although some of these books have poor science sections or unrealistic sample exams, the reading comprehension sections are almost always good) you can also use reading comprehension sections from other test prep books for exams like the GRE, DAT, OAT, and VAT. All these sections are almost identical in content and difficulty. The key is to get used to quickly understanding the type of questions asked and how to extract that answer from the passage.
You don't have to buy all the books mentioned above. Check your local library. My local library (not university library) had several of the books mentioned above. Some were a bit old (from the 1980's) but the reading comprehension section has changed the least out of all the sections on MCAT. Also check e-bay for some cheap deals, especially on GRE books. You can find good books for around $10 with shipping and handling.
My strategy was pretty straight forward...read the passage and answer the questions in the order given. Skipping those questions that posed a lot of difficulty, narrowing down the choices if I could, then choosing my first hunch. The passages on the exam will jump around from being simplisitic to complex so you can't let this throw you.
When taking your practice exams, don't forget to time yourself. Part of the difficulty with the verbal section is that people can't finish in the time allotted.
Good luck and keep practicing.