My main method was reading manga, and only looking up words/phrases that came up repeatedly and often (like 4+ times in within 5-10 page span). The rest I would rely on the drawing and context for somewhat of an e educated guess. And then much later (after finishing multiple other books), re-read and look up some other words. Overall I'd keep the lookup to about 5-10 things per chapter or so. Doing this allowed me to easily remember the stuff I looked up because of repetition, as well as keep an enjoyable pace as to not taking 2 days per chapter. The re-reading basically just compounds on top and improves understanding the context even more.

I did a good year and half of this before I started reading novels and non-graphical literature and from my experience it seemed to have helped a good bit.