So i've been searching over the net for a good program to use for flag-making, and i've found a couple:
Flag-Designer
This one is if you don't want anything complicated and hard to maker, which i've used before
Pinta
This is one is if you like to have full control over what goes on your flag, and you can use for other things like: Map-making, GE&T designs, etc.
If you guys have any other programs you think are good for this type of stuff, simply post them below, so other players who want to make their own flags can see