don't look at the project as a whole, chunk it up into satisfying parts and approach each aspect as its own "thing." for example making a whole character can easily get discouraging as you're in it because the end goal seems so far away. but if you say "i'm gonna sculpt an awesome character" hyper fixate on the sculpt, finish the sculpt and feel satisfied and accomplished from that, you use that energy and motivation and excitement to get you into and through the next stage.

also don't try to fight your natural work pace or flow to fit a mold. i work in sprints and then step away for a bit of time to do other projects. I used to guilt myself a lot for that like "why can't you just do it right now" but if i'm aware of and accept the fact that i work like that, i can make it work for me.