Here is some advice I would give to younger students if they wish to do well in their undergraduate courses.
Having been tested for many years of my life (with pretty good results), here are some rules of thumb that I feel helped me:
GENERAL
All-nighters are not worth it.
Sleep does wonders. Optimal sleep time for me is around 7.5 hours, with an absolute minimum of around 4hrs.
It has happened to me several times that I was stuck on some problem for an hour in the night, but was able to solve it in 5 minutes in the morning. I feel like the brain “commits” a lot of shaky short-term memories to stable long-term memories during the night. I try to start studying for any big tests well in advance (several days), even if for short periods of time, to maximize the number of nights that my brain gets for the material.
Attend tutorials or review sessions.
Even if they are bad. The fact that they get you to think about the material is what counts. If its too boring, you can always work on something else. Remember that you can also try to attend a different tutorial with a different TA.