Treating your projects like you would a professional one is "the secret", I think you really nailed it. Everything else is just meta. And I do love me some meta.

I use milestones, and I give myself a small award if I win, (I'm terrible, I energy-drink). Small awards help make a habit out of reaching your milestones, and you know, nothing more consistent than habit.

Hemingway's trick applies to TDD, of course: http://www.secondactive.com/2009/08/boost-your-productivity-.... I like to leave broken tests before I go to sleep, and fix them in the morning.

I don't really use anything more than git, though, and personal notes, if it's a personal project. Everything else just kinda gets in the way.