Start an agency
Sell the work before you build the software.
Building a SaaS can take months before you discover whether anybody cares.
An agency can get its first customer tomorrow.
Find a painful problem and solve it manually for someone.
Charge them.
Then do it again.
Agencies are interesting because customers pay you to learn their problems.
After working with ten clients, you start seeing patterns.
The same tasks repeat.
The same questions repeat.
The same spreadsheets appear.
The same things waste your time.
That repetition can eventually become software.
Many entrepreneurs want to jump directly to the scalable product because agencies feel less exciting.
But an agency gives you something extremely valuable:
Revenue, customers and knowledge from day one.
Instead of building software and searching for a problem, you can solve the problem manually until the software becomes obvious.