You can recommended below books for your preparation

For General Intelligence & Reasoning

Verbal and Non-Verbal Reasoning by R S Aggarwal

Analytical Reasoning by M K Pandey

For English Language

Objective English for Competitive Examinations by Tata McGraw Hill

Quick learning Objective General English by RS Aggarwal & Vikas Aggarwal

For Quantitative Aptitude

Quantitative Aptitude by R.S. Agarwal

Elementary and Advanced Mathematics by Kiran Prakashan

For General Awareness

Manorama

Make sure you go through previous year papers to understand the exam pattern and to know the level of the exam.

All the Best!!