Stay focused and don't worry about what you can't control (broader market, what other projects are doing, etc). With the caveat that it's always a good idea to have a lean cockroach plan where you could survive with a very small team or by yourself just in case.

Live far below your means. Always.

Prioritize taking time away from the screen to figure out your priorities. Meditation might help. Also probably a good idea to spend less time on Twitter (or any distracting site). This applies doubly for me too haha