If you are struggling to remember something, give up.
This advice applies primarily to rote memorization, but can also be useful for more complex critical thinking. When studying, if you find yourself working hard to try to recall a specific formula, drug interaction, or pathway, just stop and look it up. Otherwise you will only waste time and end up memorizing wrong information.
For example, if you are trying to recreate a complex diagram of metabolism from memory, draw as much as you can remember, then DON’T try to fill in the rest with educated guesses. When you have done as much as you can, take the diagram you have just drawn and crumple it up. Throw it away. Now you can return to studying the textbook diagram without the distraction of your earlier mistakes. Do this until you can confidently and intuitively recreate the diagram from memory.
**Bonus idea from Test-taking 101: if the answer doesn’t jump out to you on an exam, flag the question and skip it until the end. You might have an epiphany during the rest of the test, but at the very least you won’t have wasted precious minutes.