Hello,.
Study!Study! and lots of studies and its just simple as that.Give your most time in studies and try to stay away from distractions.Work on your weakness and strength. Stay away from social media and thing that waste your time.Do proper time management.
Good Luck

In order to score well in the board exam, You need to prepare a time table as per your convenience to divide your time subject wise & topic wise & follow it strictly.

Make notes during your study & Note down  the important points, It will help you at the time of revision.

Do practise with the previous year papers as much you can.

Do revision again after completing one chapter to make it clear.

Be confident & positive.

 

Good Luck!