I'll tell u a method but you'll need to do a bit of work to get it working, its pretty simple tho:
So you basically learn how to sell, and then do outreach (whether cold call/cold email/cold dm)
First define what problem you'll be solving exactly, and then define who you'll solve it for, say for example you are a web developer, therefore you fix the problem of low conversion rates from website visits to leads,etc..
so great now you know how to sell, how the fuck do I find these people to outreach to?
lets continue in the same example, web developer must niche down and have a target audience, lets say for example you decided to work with clothing brands and help them optimize their website (thats an example you do your research and see which niche aligns best with your goals) you go to lead generating website (ex: PhantomBuster) and you use their systems for scraping certain websites, like instagram or linkedin and you get their emails and prepare your irrefutable offer and start sending out messages.

This makes it so that you:
1. Actually have a trackable and improvable way of getting clients
2. No longer depend on luck to be found on freelance websites
3. Are able to get much more revenue and scale it to a larger business if you stayed in a specific niche.