Csilla
I will to create T-Shirt Designs!
Updated: Oct 10, 2018

Some days ago I found a really great site with adorable T-shirt Designs. I bought for myself some of them, then I realised that, the site is open for any Designers. Everybody can update designs. I had an idea, that I try myself too in this. I read about the shirt design thing a lot and I found a great article. When you are a beginner in the T-Shirt design, read this interesting article, I learn a lot:
https://www.michaelessek.com/where-to-sell-t-shirts-online/
So the conclusion is, that these are the best websites if you are a Designer and like to upload and sell your designs:

RED BUBBLE
Probably this site has the largest audience.

TEEPUBLIC
https://www.teepublic.com/join/mikeessek
This site is very popular too, so many people can see your Designs.

DESIGN BY HUMANS
https://www.designbyhumans.com/

QWERTEE
In this site are just daily or periodical Shirt Design challenges but this is a good reference.
I think I give a chance this shirt design thing, I like to create some drawing for the people! :) I'm exciting! If you have alredy experiences with this, please tell me about it! :) I'm curious what are the others opinion.
Anyway, just for fun, I bought these lovely shirts for myself on the TeePublic site. Wooow, high five for these artists! :)

This pun... :D I love it. (The shirt's site)
Finally I have a Firefly Shirt! :) (The shirt's site here)