Any successful Freelancers out there?

In order to get more useful answers, I think you need to provide a more specific definition of "successful". Here's why:

The actions someone took to get from 0 to $10,000/mo in freelancing are probably very different from the actions someone took to get from $10,000 to $100,000, for example.

I have a friend who recently got to $100k (overall income) on UpWork that I helped get some initial "social proof" by opening a small job and hiring him. He's in a niche with a pretty established product-market fit (web design). So that's one "marketing tactic" that worked pretty well for to get him off the ground.

I don’t know if I’m successful but I’m doing pretty well. I recently made the switch to agency model. So what I do is am a Twitter marketer where I help founders & entrepreneurs to grow their following on Twitter organically & build their authority in the niche.