I currently have a couple of places where I sell items and designs that I have created.
Redbubble sells shirts, stickers, and various other items custom-printed with artwork. When I make myself of a family member a shirt, I’ll post the design here as well for anyone who’s interested.
Etsy focuses on selling handmade, custom or vintage items. If I make a project where the manufacturing/shipping costs are manageable, I’ll post it on Etsy to see if others want it. They do charge a small fee for listings, so if no one buys one after a while, I will take it down.