I posted a poster design on TikTok, and I have people in my comments asking if they could buy and print it to put up on their wall. However, I don't have any way of selling it, so I ended up just sending them the full image. WHERE can I just quickly sell designs, and not worry about all of that extra stuff?
It really depends on how much you are selling them for and the quality you want and how many you need. The easiest thing to do it just have them printed locally and post them, usually the most cost effective too for small batches.
It'd be sold for cheap, I mean, I didn't expect too much traction in the first place. I just don't know where I would even begin to sell the designs
There are sites like Redbubble where all you have to do is upload a file, and they'll produce it in all kinds of formats (posters, mugs, shirts, bathmats, etc). The only issue is that they very seriously mark up the prices. So you as the creator will only see a buck or two, but the customer is paying $30.
Print on demand. Printify for example. You can build a store front through them, or link it to Etsy or shopify page. TikTok shop might also be possible, not sure.
Etsy
Google print on demand, could be worthwhile checking some of the top ones and compare t&c's prices / fees etc..
Etsy and "on demand" sites. You post your offerings, but don't print anything until someone makes a purchase.
Suggest checking out r/artbusiness.