GRE is not a test of the type for which you can spend long hours over a few days and secure a decent score improvement. It is advisable to go for a steady preparation and practice regime over at least a month or two to reach your maximum achievable score. There are books available for the GRE preparation and you can refer them to start your GRE preparation. Take help from the Books available in the market and start preparing to ace the GRE.
These days, any discussion relating to study materials doesn’t only relate to books in print but also includes content available online. The study material, whether in the forms of books or online content, required for a good preparation for GRE fall under the following broad categories.
1. Math Basics
2. Math practice – Practice Drills and Tests
4. Verbal Basics
5. Verbal practice – Practice Drills and Tests
6. Full-Length Tests
There are several books for GRE preparation in the market published by reputed Publishers. Several test prep institutes, such as Manya-The Princeton Review (https://www.manyagroup.com/gre-courses-available), have their own books containing everything together. These institutes have their own online content too. Although these books provide word-lists for GRE, it is always better to refer to a few books dedicated to vocabulary building such as the Word Power Made Easy, by Norman Lewis.
Also, the GRE Official Guide and GRE Prep material available on the GRE Official website is also very helpful and every individual preparing for the GRE must make use of.