Fairly simple, use my brain as well as the methods listed in https://nabeelqu.co/understanding to understand the material, then use Anki for any details that are useful to remember. There are lots of techniques out there on how to "superlearn" or similar, but really most of the time they have very marginal benefit, and you just need to get on with it.

Doing problems. Going to office hours. Lecture was worthless.