Practice with worksheets. Once you have mastered the flash cards, try your hand at some worksheets. Start by practicing with one number set at a time. When you have mastered all of them, try worksheets that mix up all of the number sets and see how you do. If you know your tests will be timed in school, try practicing with a timer.
Here’s hoping that now simplifying fractions for you would be easy and not so ‘trick-y’. Happy Fractions!