Typically, I learn by doing. When I want to pick up a new skill, I usually just get a book and dive right in. The repetition of the basics is what makes it stick for me.
Back in the day, when I was learning some advanced photo editing techniques, I experimented with different types of methodology just to see what it would do. I think I was going through something at the time because what began as image manipulation turned into me just experimenting and trying things for hours.
I found a few of them in my ongoing process of going through old work. I remember how much fun I had while creating them. Just digital doodling without a care in the world.