What is the most important skill, technique, or concept that, if practiced, will yield the most results in terms of advancing your level of art? Is it the proportions of the figure? Value? Line quality?
I am trying to become a better artist, and I know I need to practice. I totally get that. Practice, practice, practice. My question is, if I have an hour after work, what is the best use of my time? I'm very curious what the artists here have found to be the two or three concrete skills that really helped them take their art to the next level.
Any advice is very much appreciated!