First, you have to ask yourself what're you providing as an editor.
I thought I didn't need one for my first works. Mainly because of my personal process of self-edits, proofreading, alpha-readers, and AI writing assistants were all I thought I needed. Then, I met one of my readers who understood what I was trying to say but made it increasingly better with the same flow. I hired them as an editor, and I feel the work I'm putting out for my paying audiences is much greater with a second pair of eyes with the same mind peering through the lenses.
My advice, as an author who's now a firm believer everyone needs a personal editor rather than someone random and only good due to reviews - Go work with someone's book in a genre or scope you're genuinely in love with and interested; Then put your passion on display so potential buyers can get a general idea as to who you are and what you're offering.
You can be the best editor in the biz, but if all of your editorial pieces are about romance, and I see you correcting kisses/smooches, sex scenes, etc., when I don't have the need, I won't be interested. Then, a double-no if I write in genre and I don't see anything special going on with your suggestions (pacing, characters, plot, etc.)
I was talking to several author buddies who were also looking for editors, and these are some of the stripes we had from a consumer's standpoint. To be honest, this website is probably your best starting point. Go to some books that interest you but are missing a particular aspect. Then re-write them, and send them to the author. If they like it, you have some business; If they dislike it, you have source material for other clients.