There’s an incredible wealth of GMAT prep material out on the marketplace. Private one-on-one tutors, endless prep books, online and in-person coursework, countless Internet resources… sometimes it almost seems as if there is too much to choose from. With so many available resources, how do you decide which ones are best for you?

Diversify your prep materials

Most financial analysts will tell you that one of the smartest things you can do with your investment money is to diversify your portfolio. All this means is that it’s wise to try a few different types of GMAT prep material instead of relying on just one—you know, the old don’t-put-all-your-eggs-in-one-basket bit.

The Official Guide for GMAT Review

Most test takers pick up a copy of the Official GMAT Guide, issued by the Graduate Management Admission Council (GMAC). The book isn’t expensive, and it’s the go-to resource for nuts and bolts GMAT information: how the test is set up, what it contains, and what it’s for. The Official Guide also contains a ton of practice questions taken from past exams and a diagnostic test.

Online GMAT resources

There’s plenty of great GMAT prep material floating out on the World Wide Web. Discussion forums, pages with tips and tactics, video lessons and problem explanations are all available and, often, free. Keep an eye on how you spend your time, though—just because there are lots of resources out in the digital ether doesn’t mean they’re all accurate or useful. Seek out the good stuff and use it in conjunction with other quality GMAT prep material.

Test prep courses and tutoring

Many students choose to enroll in a test prep course or hire private help. There are plenty of options available, ranging from elite costly private GMAT tutors to customizable online GMAT prep courses.

Knewton’s online GMAT test prep course delivers live and on-demand lessons, as well as practice materials based on your personal needs.