This has probably been mentioned numerous times, but it really is the key. For me at least.

It can be anything, as long as there are targets and goals set to work towards. For me personally, my favourite project was refurbishing an old guitar. Apart from playing, I knew next to nothing about the manufacturing processes etc used, but learning all this added to the entire experience. But I found lesser things also worked, like redecorating my room, reorganising my bank into separate accounts and so on. Right now I'm weight training with a goal of filling out my shoulders.

Sometimes it's difficult to make the first step if motivation is pretty low. But if the first step can be made, then it's a great outlet and there's a reward at the end.

Just thought I'd contribute with some advice that works for me.

Peace out.