5500 words?! Most GRE books only emphasize the most common 350 to 1500 words, 5500 seem to be slightly excessive. If you don't have at least 3 months to read that book (still about 60 a day), shift to some other that feature less but more selected GRE vocabularies.
Focus on learning word roots. Stay away from a long list of words in alphabetical order, instead, go for ones that display the meaning as well as the word roots (prefixes and suffixes) of the vocabularies. For example, bene is a prefix that means "good" and it forms words like bene/fit, bene/fiter, bene/ficial, bene/faction, bene/factor or bene/factress, bene/dict (blessed), bene/diction, bene/fice, and bene/volent, etc. That way, you can absorb many more words in one go.
Use flash cards. Thousands of words are hard to review, you can either buy the ready-to-use GRE flash cards, or make your own. Keep the pile with you and review whenever and wherever possible.
Take a mock exam. If you have not researched what taking GRE is like, I'd recommend trying a mock exam just to familiarize with the environment. You can check the GRE site to see if they have one available. Major tutoring companies may also be able to provide a few if you enroll in their prep courses. I have never gone to those commercial prep school, but if you're time-pressed having some professional help may not be a bad thing.