How about a thread for good tutorials / infographics? They can be of any sort, preferably ones you yourself found useful at some point.
As common as the meme "there are no shortcuts in art" is, technique is basically an artist's shorthand, and these can be taught. There are usually tips and tricks that are effective for learning, sometimes just simple things you wouldn't have thought of, some complex, so let's share some.
I'll start with some Loomis stuff because that seems pretty uncontroversial. I have folders of tutorials but most of them I saved when I was just starting out, so I might need to vet out the useless ones.