psychometric test is a screening tool and many high scorers may also get rejected in it. This type of test is used to assess the attitude of a person. What we usually do is that we try to be honest and expose our faults such as anger, one track mentality and poor interpersonal skills etc. What you need to do is to keep consistency in different type of questions that are designed to gauge a particular variable such as honesty or emotions.
try to spot questions are are checking a particular attribute and try to be as positive as possible.
I hope that would be helpful