10 years ago I would have to gone to the live drawing class of some kind, or at least set up the scene with a bunch of random stuff, get some consistent lighting and draw for hours.
Now we have something called internet - the largest instrument ever developed. We can find references for pretty much everything that can be drawn.
Want to draw an elephant? - Google > elephant > lots of references!
Want to draw cute girl portrait? - Google > cute girl face portrait photo > lots of references!
Want to draw some mountain environment? - Google > mountains > lots of references!
But what if you want to do some SIMPLE value studies, with SIMPLE shapes and SIMPLE lighting situation?
Well finding that may be not so simple - even though you'll probably find hundreds of pretty decent photos, you may find nothing that suits your needs. What then?
Answer is rather simple - 3D. You can use, for example, Blender for setting up simple scene. Half an hour, two tutorials from YouTube, and you're good to go. You won't be pro after such a short time, but it'll be enough for creating something simple. Render stuff you want to draw from any angle you wish and draw.
Learning some of 3D basics won't hurt, and really can help you.
Any ways, I forgot to save my process, so I've got some scraps of layers that I didn't delete.
That's it.
