Everyone's different, but something that helps me is deliberately testing myself after reading a passage or chapter that taught me something I didn't already kn

Everyone's different, but something that helps me is deliberately testing myself after reading a passage or chapter that taught me something I didn't already know. Literally take your eye gaze away from the page and try to recall, summarize, and answer a question about what you just read. It's one of those things that sounds too simple to be effective, but it works for me.