Remember that drawing isn't a race. You can try jam packing your schedule with all sorts of things, but you'll get burnt out if you do too much too fast. Not every aspect is going to take the same amount of time to hammer into your brain. I sure learned that the hard way.

Structure is a good thing. I have a Word document that details my goals for art and the things I want to learn. However, I don't have a set schedule of when I should learn those things. What I do is give each exercise my complete focus when I can, making sure to do it to the best of my ability. When I am finished with said task, I move on to the next, again, when I can.

Of course, just because I finished doing an exercise doesn't mean I'm a master at it. I might warm up by retrying to do parts of the exercise again, or apply my knowledge to something I'm doing outside of study. Keep doing this for years and you're gonna learn a lot. I think this is the best approach to learning art.

Take a look at what you want to accomplish and start somewhere. For Drawabox, Lesson 0 is where you start. Go from there, and in the advancing lessons take each exercise as it comes, doing your best with each one. Make sure to get feedback from people as you complete the lessons.

Just keep moving forward with your learning, regardless of the outcome. Hopefully you found this helpful.