What works for me is dedicating large chunks of time either on my weekend or after work, drinking some caffeine, and also taking breaks about once every hour for super dense stuff or every couple hours for less dense stuff.
Highly technical stuff is very hard to get into the frame of mind for and so you don't want to be doing stupid little 30 minute sessions over and over because that wastes warm-up and cool-down time. IMO, much better to get warmed up and then take in as much as I can while my brain is fresh and ready.