You can use water colour pencils, paints or even markers to colour them in but they are so funny and full of character, you can use them for pretty much every occasion. I have done a birthday card, a book mark and just a cool little image to display in my craft room.
I'm sure I'll find more ways to use these crazy little guys so I'll post when I do. Do yourself a favour and get a hold of these stamps before they're gone! Have fun.