I'm trying to avoid a gap on my resume. After leaving my previous employer I've been working on multiple businesses concepts over the course of two years. I researched each business individually before finding the one that worked and launching it.

I have only been working on the successfully launched business for less than a year, but I've been paying my own way (self employed?) for the entire two years while working on those other business concepts which didn't pan out.

What is the correct way to list this time span on a resume?

Do I attribute the entire two years to the current business?