Another path is having a unique story that you can raise money on. A significantly sized problem that you are passionate about and have unique domain experience with. You can potentially acquire this unique experience via strategically picking where to work prior to starting the company. Such as taking a smaller salary specifically to get said experience.
The other path is just busting your ass working for someone else for awhile and building your war chest before going out on your own. Save up at least 1 year of living expenses.
For reference, I've done a blend of #1 and #3. Though in hindsight I wish I did more of #2. Having unique domain expertise gives you a competitive edge.