As you want to appear in IAS Entrance Exam and looking for preparation tips s for it I would like to say You need focused study of subjects.

You should analyze the syllabus, and hard work is needed to crack this examination.

You need to have good knowledge of current affairs and our history and administration.

It’s important to have some reading habits as that will help you to keep yourself updated about the current affairs. Read lots of magazines.Also you should be strong in aptitude and the subjects that you have chosen or will choose.

Take frequent short breaks.

Space out your studying so that your long-term memory retains it

Don’t try to memorize everything; make sure you understand the material well.

Listen to relaxing music to ease the boredom of studying.

Don’t study later than the time you usually go to sleep

Here I am also telling some good books name of preparation of this exam

Best Books for IAS Exam;-
IAS Prelims/CSAT Civil Services: 18 Years General Studies Topic-Wise Solved Paper(1995-2012)
by
Disha Experts
Publications: Disha Publication

The Pearson CSAT Manual 2013: Civil Services Aptitude Test for the UPSC Civil Services Preliminary Examination
by
Edgar Thorpe, Showick Thorpe
Publisher: Pearson

UPSC Portal CSAT Comprehensive Manual: IAS Preliminary Examination 2013 (Paper - 2)
(Paperback)
by
Sachchida Nand Jha

IAS (Pre.) Solved Papers General Studies wih CSAT 2011 & 2012 (Paper - 1)
(Paperback)
by
Expert Compilations

UPSC IAS Civil Services Exam 2011 Syllabus
by
Gkp
Publisher: G. K. Publications Pvt. Ltd