Take a test first! Figure out what your specific strengths and weaknesses are, then use that to guide you. For your weakest areas, start with Foundations of Math (and that might be most or even all areas!). For your stronger areas or as you build your skills, use the regular books, but go back to Foundations of Math whenever you run across a topic in the regular book that's giving you trouble.
In the regular books, concentrate on the regular chapters - ignore the "Extra" chapters (for now - maybe you'll do some of them later). Your goal is to get a basic foundation across all of the topics and then work up from there.
This is the order we do the books in class:
Fractions Decimals and Percents
Algebra
Word Problems
Geometry
Number Properties
Read these two articles:
https://www.manhattangmat.com/blog/inde ... lly-tests/http://www.manhattangmat.com/blog/index ... -the-gmat/Next, the below article talks about how to develop a study plan. I just rewrote this one and the new version should be up on our blog in the next week or so, but you can start to use it for now, then check the blog periodically for the new version:
http://www.manhattangmat.com/blog/index ... an-part-1/Check that all out and then come back here with any questions!