Look dude, it's GREAT that you enjoy making these for people. Continue to do so, some people like it. Just know, Paint is NOT the program to use. Paint is fine for pixel art, and some very basic editing, but it is not the program you should use for something like this. I'm assuming that you are someone younger (Under 18, and I'll predict you are in the 11-15 range), so you should continue to do this, and practice. Paint is great to start out, and show your friends what you can do. Look up skins online and recreate them just how you are. Yes, they won't look that good, but that's because of the program. Paint doesn't give you much to use, especially if you are new to it. So just keep practicing, and later move onto programs like GIMP, Paint.Net, or even Pixlr. These programs can add shading, and texture to the skin. Also, try to make things proportional and even!! You'll be able to do good, but it will take practice.