How To prepare for English:
English: For English you need to improve your vocabulary and grammar for any competitive exam.
It will take time to learn the vocabulary but it will help you in around 20 direct questions of Synonyms/Antonyms and instead of that it will help you in understanding the passages ,PQRS type questions and in Vocabulary based fill in the blanks. Almost it covers all the topics other than grammar based questions.
For Vocabulary first start with news paper ,Read it and note the meaning you do not know, when there is collection of above 500 good meanings (learn on the daily basis) then after that you will start learning directly with any good vocabulary book like I found PT education’s (VA Atlas) book good for this purpose.
For Grammar you need to first read the rules(not try to learn them, Read them 8-10 times on regular basis) from any good book and start solving the error related problems as much as you can by maintaining the balance with other parts of course.
Book lists for English:
1.PT education’s (VA Atlas)-Along with meaning of that word this book also contains all possible synonym ,antonym ,word usage in sentence at same place.
2.The best way to learn the meaning by some key word or by the help of some images. By this we can learn the vocabulary easily. Book For this: VoLT ,Vocabulary learning techniques By Abhishek Jain
Follow any good book which have along with exercise , there solution in Detailed Manner.I have read many books for this but I found best one is:
After practicing from these books , now time to solve the questions which asked in UPSC previous papers :
Solve IES ,CDS,SCRA 10 year English part questions: