Feel free to use however you'd like, please credit me if you use! :)
You mean something like CC0 or credits are required?
I think I recommend you "pastel" tag
Yeah CC0 means public domain. CC-BY you must be credited but without copyleft, CC-BY-SA is CC-BY with copyleft
You are not bound by using existing licenses. License is a "contract" between you and user.
In general you can write something like this:
License:
- You can do X
- You can do Y
- You can't do Z
And it will be "considered" as license so you can use your any custom license. In general it consists of following parts
- Must user attribute the author?
- Can user modify the art to suit their needs?
- Can user redistribute the art?
- Can user use it commercially or only non-commercial use is allowed
But some creators use free cultural licenses usually from CC (Creative Commons) family