Practically, one way to do that is to go sell a product that doesn't exist. And I mean sell it, not just get feedback. Get an actual contract from the customer and their buyin to help you build out the concept.
Build a high ticket item- this probably means a b to b product. You need as much skin in the game from your first customer as you can get and cheap products wont get it done.
Getting this contract is difficult, and the people i know who've taken this route admit that their first contract had hole a mile wide that allowed their customer to walk at any time. But, it sets the scene for collaboration and puts some psychological incentive out there to help keep everyone interested.
Only after you've sold your first customer do you then hire coders. Since your money will be somewhat fictitious at this point, you may have to look for a founderish type of coder, but thats ok. It will be bucket loads easier (and cheaper in terms of equity) to find one with a contract in hand.
I know someone who's done this twice, and both times, he achieved huge exits without outside substantial outside funding. The products were boring, but the businesses were outstanding.