I discovered that there are ways to study that are better than others, I'll try to share those better ways I have found, why not share yours so we can all learn?.
Anatomy or anyting else you want to draw from memory:
- Bad way: Copying reference as good as you can is not a great way to memorize anatomy, it will train your eye and hand coordination, but it won't necesarily make you learn the parts you are drawing. I have personally draw docens of sheets full of anatomy and I can assure you I learned almost nothing from it, beign unable to reproduce from my mind what I just drawn.
- Good Way: Aim for memorization of simplified forms, part by part. For example, don't try to study the whole head at once, first try to memorize the shape of the eyes, try memorizing the proportions, the lines, the angles, when you have memorized that you can go on to learn the nose, the ears and so on.
The most important thing is to know how to memorize. The best way I have found is, first copy the reference as best as you can, then forget about the reference and do your best to try to draw what you recall from memory, you will notice that there are certain things you do not remember, only when that happens you can go back to the reference to see how it is drawn, then when you know what to do, continue to work without reference until you encounter another part you do not know how to draw, and repeat this process.
The important thing is that when you check the reference from time to time you have to try to "write" that small part of the reference in your mind, do not go back to drawing until you can clearly see that small portion of the reference in your imagination, our minds can memorize very simple forms much easier than complex ones, so try to memorize bit by bit.
A good training/proof for this is to draw a small line in a paper, then try to memorize its lenght and angle, then put your hand on top of it so you cannot see it and then try to copy it from your imagination. You can do this as many times you want as a warmup for this method.
When you finish the drawing you can make a mental check list of the parts you had problems with, and re-check them with the reference. Try to see which parts are done badly and try to correct them by making another drawing again without looking at the reference. Repeat the process you did the first time again and again until you can draw the image without any need to look at the reference (it won't take that long i assure you!).
Doing this method you can learn things extremely quickly, but it is hard to the mind, so, no matter how much boring it gets, keep doing it until you memorize all the info. The smallest things you pick to memorize, the easier it gets. The simplest (forms without much details) things you memorize, the easier it gets. So try to learn something small step by small step until you get all the figure memorized.
For example, with this method I got to memorize an image of the nose in 8 tries, in more or less than 1 hour.
I try to add more things in the future, but this one is one of the biggest things I discovered, you should definetely try it.