1. Don’t ever make negative sentences. Always make a sentence that is positive in the meaning, even when there is a word which conveys a negative sense. For example: the word disturb conveys a negative meaning in itself. .
2. Do not use ‘I’. Use of such words should be avoided. Excess use of ‘I’ can reflect that the person is self-centered which leaves a negative impact.
3. Don’t use famous Idioms or phrases. Use of such famous lines shows your lack of imagination and thinking capacity.
4. Also one should avoid sentences that are preaching or very bookish. Also negative sentences should be highly avoided.
5. Positive sentences should be written. The sentences should always be written in legitimate handwriting. As time is short, so you have to write fast. Practicing only would help in that scenario.
6. You have to be honest and write sentences which come to your mind first. Although, in fifteen seconds you cannot mask your natural responses. So, practice as much as you can. Start by collecting words for the Word Association Test from the internet. Make sentences based on them in the given fifteen seconds of time limit. After you have done it for sixty words, check your response thoroughly and try to see any mistake that you might have made. While practicing again, make sure you do not repeat those mistakes again.