TNEA consider boards marks in order to provide admission. There is no entrance exam. 

In order to get admission in top colleges through TNEA you need to perform good in your boards exam.

To score good marks you should plan your study. So, that you can complete your syllabus on time and you get proper time for revision. You should be aware of your strength and weakness. 

Refer your text book focus on the topics which carries more weightage in the exam. If you want you can also make your important notes which will help you at the time of revision. 

Revision plays good role in scoring marks make sure you don't neglect it.

Solve previous year papers to understand the exam pattern and level of the questions. So, that you can prepare accordingly.

All the Best!!