Generally, whenever you want a metal element, accent, or embellishment in your scrapbook page or card (or other craft): photo corner, 3 in a row, to draw the eye to ut intended focal point... Most people attach them like paper clips. I like the whole spiral showing, so i adhere the with adhesive. I'll post a few example pics in a little bit. :) Hope that helps!
I hope the pics help... I love adding metal (or shiny or wooden) accents. it works best for me using the rule of three which naturally guides the eye from 1 detail to a 2nd, and finally to the focal point. HAPPY CRAFTING! :)