That's a good question. For myself, I've been implicitly applying many of the principles I learned in 37signal's (free) book "Getting Real". Especially the parts about being lean and prioritizing tasks.

Another aspect that keeps me sane is constantly deploying updates. This might not apply now as you're building up to your alpha. But I find having too many features "on-deck" takes up brain cycles. And just getting it out live takes a load off my brain that allows me to focus more on new features.