1. Normally Affiliate buttons are 88x31px, but to get a nice background fist we shall make a bigger canvas. So open a new canvas (300x300px), press ctrl + D to reset your colors and go to 'filter' > 'render' > 'clouds'. Now create new layer (ctrl + shift + N) with your second layer go to 'filter' > 'render' > 'clouds'. Then 'filter' > 'distort' > 'twirl' and use this settings:
2. Repeat "with your second layer go to 'filter' > 'render' > 'clouds'. Then 'filter' > 'distort' > 'twirl'" using these values:
3. Now put set the blend mode for layer 2 + 3 to overlay, select the rectangular marquee tool and set it to fixed size.
4. Look for a nice piece you want on your button and when you find it press 'ctrl + c' (copys).
Open a new canvas with 88x31px and press 'ctrl + v' (pastes)
BTW: Don't forget to press 'ctrl + shift + e' (merge all your layers). Otherwise you'll get the effect from 1 layer alone.
5. Now you're done with the affiliate button, ('ctrl + u' to add/change colors), here's what we came up with:
