In order to achieve good marks in your board firstly make your time table and here are some preparation tips you can follow given below:

Make your time Schedule & divide your time in two parts first your daily routine & second your study time which should be devided subject wise & topic wise as it will help you to cover all the syllabus.

Do practise also as much you can.

Make your own notes as per your convenience and note down the important things from the particular chapter as it will help you at the time of revision.

After completing the chapter do revision again to make it strong.

Be confident what you prepared.

Good Luck!