The key to clear Math papers at Anna University is studying the previous 5 years question papers thoroughly. Firstly determine which are the main topics covered repeatedly and start practicing them. Learn all the important formulas You can also refer to the internal tests paper in your college. If you compare the internal paper with the previous year's papers you will find certain topics are repeatedly asked. These topics demand the most focus.
Apart from this if you have any class notes try solving those questions. You can also refer to the previous year's questions mentioned in the math textbooks. Refer to local authors only as they will be more than enough.
Lastly, a practical subject like Math requires a lot of practice.