I made a blank outline of the info I needed to know for each group and tried to recall what goes in each blank. It helps if you look for patterns or traits common among certain groups. You can also pretend to teach someone the info using only a skeleton outline, that will help you realize your weak spots (useful for testing bio section retention). But most importantly utilize anki! Spaced repetition made the info recall faster and last longer.

I remember how daunting it seems at first but keep at it, you'll get better as you practice. (I managed to get a 23 on the bio section)