I found time by picking something I enjoyed doing - turning my hobby into something more, and occupying that time plus some more. And then honestly I prioritize

I found time by picking something I enjoyed doing - turning my hobby into something more, and occupying that time plus some more. And then honestly I prioritize it over getting great grades in my classes, because even if it fails I'll still get a lot more out of the experience (personally) than sitting in a lecture or checking over the answers of a problem set. I bootstrapped with about $3000 of savings, and run a lab at school that's a bit of extra income. Pick the right market and be smart with your suppliers and revenue can start coming in pretty quick. But you're right, time is the big thing stopping me from growing faster... I worked full time last summer and that pretty much stopped me from doing new R&D work, this summer I'm going to be working on the business full time, we'll see how it goes!