Hi there, I'm Diana with my handy dandy tip for you today!
Don't be afraid to stamp on air dry clay! It's easy. The best way to do it, is when the clay is still soft. If you want, you can LIGHTLY dab a little bit of pigment ink, or even a bit of olive oil, to make sure your stamped image makes a clear impression and the stamp won't have any bits of clay in it.
And that's my tip for today! Craft on!