how to avoid silly mistakes

How to Minimize Silly Mistakes in Exams?

Have you ever missed a zero, or added instead of subtracting, or put the decimal in the wrong place in math paper?

Have you ever failed to answer a question fully because you missed one of its sub-questions?

Have you ever misread a question and, as a result, answered it in a tangential direction?

These are all silly mistakes, and they’re big sins because you lose those marks which were 99 percent yours.

How do you avoid these careless mistakes in exams?