Different things work for different people, but I'll give you my two cents. I got through college entirely through self study. What works for me is reading a t

Different things work for different people, but I'll give you my two cents. I got through college entirely through self study. What works for me is reading a textbook and re-writing out any concept in the textbook in my own words until I understand it. Afterwards I do practice problems or a project to ensure I'm not lying to myself about my understanding. If I can, I only do one topic until I'm sure I've solidified my knowledge to a sufficient degree that I won't forget it when I shift my main focus to something else. Lastly but most importantly is be ok with failure. When you fail to learn something, take a break and then come back approaching it from an entirely different angle.