I use these skins on Macs and PCs.
Pretty much foolproof.
But here's some tips I've learned:
1. Use a VERY dilute soap on a damp paper towel to clean body oils and grime from the device.
2. Power up the device so that it is warm and dry before application.
3. Go slowly. If you can get a third person to support the skin while you use two hands to align on an edge, do so. Do not overlap edges, even by a 'hair'. The skins are designed to fall just short of the edges.
4. Press everywhere firmly over the entire surface with a blunt object, such as the smooth bottom of a shot glass or tumbler, even if you think this is a waste of time. You are getting the best coverage of adhesive this way.
5. Power on the beautiful new skinned device. Let it warm up and 'set' the adhesive.
6. Post pics. Show some skin.