Dimitrios Saravacos

Practice, practice and practice.
Loads of problems and in depth discussions in order to find and address the weaknesses.
In time limited environments, like exams, weaknesses always surface.
I have coached first-year math university students filling the gaps in their education.
It is difficult to teach math to just pass an exam. It usually ends in dissapointing results.
This is why exploring and filling the gaps in the knowledge and logic is important.
The latter requires extensive experience and wide knowledge of the subject.
Of course , this also requires some aptitude from the student in order to comprehend the difficult concepts.