Dear Zoro,

In order to prepare for GUJCET you can refer your text books it will help you to clear your basics.

For Mathematics you can also refer to RS Agarwal and I.A.Maroon.

To score good marks in your exam you should also solve previous year papers to understand the exam pattern and to know the level of the exam.

Solve as many as mock test series for your practice.

All the Best!!