I have the simplest set up you could imagine. I just use a Brother MFC-J4440DW printer, the same printer I’ve used for years to just print text documents and some glossy Kodak sticker paper. The printer was a couple hundred bucks and the paper is $10 for 10 sheets. I charge anywhere from $15 to $25 per sticker and usually get 4 stickers per sheet of paper. I then cut them out by hand using an xact-o knife. I’ve looked into automating the cutting process using something like. Brother Scan’n’Cut or a Cricut but I honestly enjoy the manual process of cutting stickers so I’m sticking to it (pun intended!)
There was a little bit of trial and error to get the level of printing quality I finally ended up with but now that the settings are dialed in it’s a very easy process. Drawing the art is the hardest bit. I just use an iPad Pro with the pencil and Procreate for that