As you stated, spend as little as possible. Make every penny cry. Jeff Bezos had all his desks for himself and his employees made out of old doors put on legs - they built the desks themselves.
https://bucket.trending.com/trending/twitter/2018-01-28/the-...
Bill Gates only flew coach until 1997 when he was worth $35 billion. You think you have to ride first class? Why are you so special when Gates was riding coach until he was up to $35 billion?
Mike Tyson earned 1/3 billion dollars and blew it all and declared bankruptcy. Johnny Depp has made $500 million and almost went broke, doing shit like spending $3 million on Hunter Thompson's funeral, where he shot Thompson's ashes out of a large cannon.
You need to start earning cash immediately. Make sure you get some clients before you quit your job, if possible.
If you are really successful, don't be a douchebag - pay everyone a fantastic salary, even receptionists and data entry people, like, $80,000 minimum for everyone.
This guy was making $1 million per year, but his secretary was earning $40 and so were others, and barely making it in life. So, he paid everyone $70,000, including himself. https://www.bbc.com/news/stories-51332811 Be this guy.