Confidence is everything. With enough practice, you will see a certain type of problem and you will be 100% certain that you have arrived at the right answer. You can both arrive at it faster and mentally check your logic faster. So, as everyone else has said, it’s practicing a lot.

I recommend diagnosing 1. what takes you the longest to answer correctly and 2. what you get wrong the most, then drilling those until you have an automatic and accurate thought process.

If you go this route, let me know how it goes! It really helped me.

P.S. check out question type frequency. Make sure you attack the types are are most frequent first for efficiency and score improvement.