All GATE papers consist of compulsory sections of Maths and General Aptitude along with English. It is advisable to prepare for these sections don't neglect these sections along with main syllabus. These are easier sections to score good marks in your exam. 

In order to start your preparation you should be aware of the complete syllabus, exam pattern and important topics. 

Always recommended good study material for your preparation.

You can make your important notes which will help you at the time of your revision. You can also make your formula book. 

Solve previous year papers to understand the exam apttern and level of the exam. 

To check the complete syllabus and recommended study material you can refer below link

https://engineering.careers360.com/articles/gate-how-prepare-for-mechanical-engineering-me

All the best for your Preparation and Exam!!