and the explanation by Morpheus_X is totally wrong.
in roder to change the armband, you have to learn a bit about making kits.
extract the kit you want to edit and have it as BMP then open it in a major editing image program such as PSP or Photoshop and change the paint over the armband with the color you want.
if you do it just like that, you'll lose the texture, but it'll work.
once you learn how to make kits, you'll be able to just change the color and still keep the texture or even make difrfent styles of armbands.
Exactly, I agree with Maleato. Paint is a universally available tool, and everyone is familiar with it. If you just want to make an armband, there's no need to download the whole trial version of Photoshop or PSP just for this. You might as well just use Paint.