In order to become a IAS officer you need to apply for civil services exam conducted by UPSC. It includes prelims, mains and final interview. To become and IAS  officer you should have the following qualifications

ELIGIBILITY :

Candidate must have complete their Graduation degree from any recognized University, Final Year student can also apply for the exam.

Minimum age limit is 21 years and Maximum age limit is 30 years.

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Here are some preparation tips you can follow for the preparation:

Go through the previous question papers: Go through with previous year papers as it will give you an idea about the exam.

Make your own notes: It is always advisable to make notes of the related topics as you go through the books and other study material. A well drafted note solves two purposes.

Strategy for General Studies: General studies paper is equally important for Prelims and Mains examination.

History: It is a huge section & Also emphasis is given to Ancient India. A cursory glance over the medieval history is also necessary.

Geography: In this there are physical geography and maps related questions. So get yourself well-acquainted with maps with the help of a good Atlas.

General Science: It covers a major chunk of this paper and a standard guidebook can make you well-versed on the topics of general science.

Current affairs: Going through a standard newspaper daily can keep you updated on the current affairs topics.

General awareness: Any good guide book or year book will help you cover this segment.

Good Luck!