Welcome to my forum!
Hey, DevForum! How are you? I’m fine! Since I am specializing in GFXs, I’m taking commissions! My examples can be found below, same for the prices!
Who to contact:
Interested in hiring me? DM xMapy#0001, if I am offline please be patient, I’ve a life!
Prices:
Group Logo: 100 
Icon: 100
Thumbnail: 300
Youtube/Twitter/etc. banner = 500
Sincerely,
xMapy
DevForum Member.
Very basic and boring, if you want to sell designs you gotta have more experience. But anyway, gl with sales 
Alright, thank you fr your suggestion.
Hey! As much as I believe you have potential, I think you should wait a bit before selling your designs. You can’t just add “rainbow clipart” and slap some text and a basic pattern as a background and expect someone to pay 100 Robux for it. Before you start selling your designs, I would practice a bit more.
You have potential but I have some suggestions for you.
-Dont use free vectors from google, they might have copyright or customers may not like that you took those images from google.
-Try usign shadows and Use some contrast options so it looks better.
-add strokes, inner shadows, etc… to text.
And another suggestion keep working on it and be one of the best Graphic Designers on Roblox.