Practice - Although answer writing is essential for any UPSC civil services paper, it gets double the import in the maths paper. Practicing makes you faster in your problem-solving.
Avoid silly mistakes - Avoid silly mistakes like ignoring a ‘+’ or ‘-’ sign, copying numbers wrong, or making simple addition/subtraction mistakes. These can be very costly. Practice till you are perfect.
Go through a problem carefully - Write down what is given in the question. Then work out the answer step-by-step.
Present your solution clearly in steps, line-by-line - Always write the solutions neatly. Don’t make the examiner’s work harder by providing haphazardly written answers.
Always understand the topic - Never try and learn the process by heart. It doesn't work in mathematics.
Always understand the topic - Always understand the question correctly before venturing to work out the solution. Once you start writing the answer and it is incorrect, you lose precious space in the question-answer booklet.
Prepare and keep a formula sheet - Always prepare and keep a formula sheet handy with you. This will help you memorize certain formulas that would be required to solve the problems.
Always solve mathematical problems with a relaxed mind - Panic can cause confusion and you will end up crying badly on your UPSC optional paper.