Started creating basic models for the art for Mech Parts in Blender. Since Blender is free it’s a compelling choice, plus I have a little bit of experience with it. Since I’m only making simple models to just import into Paint Tool Sai, I can use it with no trouble on a relatively weak computer.
If you want to use Blender, the best piece of advice I can give is to start with a tutorial that just explains the interface. It’s not super exciting, since you don’t get to make anything, but it will help a lot since Blender’s interface is like a vast forest.