What I found really helpful for university lectures was to write down as much as humanly possible (in the form of free hand notes on the computer) after the lecture, without taking notes during it. Usually I'd get stuck after a few sentences but then remember a whole bunch of concepts attached to that sentence and start writing for a while.

I'd then go back and find any gaps or things that I was unsure of or didn't make any sense and then study those with extra caution. It was a very mentally-intensive exercise but it had proved the most successful study technique thus far in my academics.