Ask HN: How to leave my startup after my stock vested?

I'm leaving because of personal reasons, I still believe in the future of the company and would like to make my exit tidy. After 4 years, the vesting schedule is over, and I own approx 40% of the company. I only have 1 other cofounder and some investors. What do you recommended to do in this situation? How should we structure my transition out to ensure the company keeps running smoothly (decision-making, compensation, incentives)?