The GS paper in ESE is very important and can be crucial for determining your rank. Here is the list of topics from the syllabus and preparation strategy.
Engineering Mathematics and Numerical Analysis - Made Easy Mathematics book. This contains a lot of solved problems for practice.
Engineering Aptitude - Made Easy Aptitude book to learn some new tricks and shortcuts for faster solving. This is a fairly easy and high scoring topic.
Material Science -
General Principles of Design, Drawing, and Importance of Safety - You can follow any standard textbook from Made Easy/ACE or IES Master or class notes. Visualizing things plays a very important role to achieve success in this topic. You only need theory to learn definitions, technical terms, and formulas.
Information and Communication Technologies (ICT) and Basics of Energy & Environment- Saurabh Sir and AP Singh Sir’s (Made Easy Faculty) note is enough to prepare for these two topics.
Basics of Project Management, Standards, and Quality practices in production, construction, maintenance, and services- Any standard textbook from Made Easy/ACE or IES Master or class notes will serve the purpose. Students from the Electronics branch score well on these topics.
Current Affairs - You do not need to focus a lot on current affairs. Be aware of the things happening around you. Instead of reading the entire newspaper install news apps like Inshorts or Jagran Josh
Ethics and values in the Engineering profession – You can follow the Lexicon Ethics Book but this subject is logical and there is no need for any book as such. Just be logical and think for yourself what’s ethical and what’s not.
Lastly, constant revision throughout the year is essential. You should go through the entire syllabus at least once a month. For GS preparation group study can be also helpful.