First of all u have to meet minimum eligibility criteria of this exam that is:
You must have studied maths and english as a compulsory subjects in class 12th.
Minimum percentage is required in board exam which you can see at the time of form filling.
Forms are out in the month of may generally and examination is held in the month of june.
After cracking the exam you will be shortlisted for the selection. In which your exam score and class 12 score is added. 65 percent weightage is given to entrance and 35 percent to your 12 th marks.
After that colleges are being alloted.