After college I spent six years working at a good tech company. In addition to a lot of great learning, it allowed me to build a big financial cushion. I continued living on a graduate-student-like budget with a software engineer salary, so I saved about half my after-tax income.

This generates one year of runway for every year worked. But my savings also grew thanks to some solid investments, so after six years I had ten years of runway.

Over the subsequent four years I spent down about 30% of my savings while working on startups of my own (I made some revenue, I took some small angel investment). Relationships and expertise that I built in the process allowed me to pivot into running a lucrative consultancy.

Before somebody says "you can only do that if you're young and unattached", I will add that I got married before I finished school, and our first child was born the same year I quit my tech industry job.