Work 3 days per week for someone else. This relies on you being a trusted and valued worker for the firm who allows you to work 3 days. So work hard at your job and the management will likely be okay with you asking. That's what I did for a couple of startups. Having a work-day or two available for work-time meetings with customers and lawyers / suppliers makes a large difference. People treat you more seriously when…
I am doing this - working 2 days/week for my previous employer and it works really well... eases out the initial cashflow problem.