Custom-cut adhesive strips are shaped such that they install onto a device in only one way. When orienting your adhesive, look for distinct cutouts or markings that hint at how to place the adhesive:

Most adhesive strips will have a neutral/clear liner covering one side and a colored liner covering the other. You'll be peeling the neutral/clear liner first and applying the exposed adhesive to its corresponding surface.

For example, if your back cover adhesive's clear liner faces the phone frame, you'll stick the adhesive strip to the frame first. If the clear liner faces the back cover, you'll stick the strip to the cover first.

If the adhesive comes in pieces, match each piece to the device by its contours and set them next to your device.

To ease the process of removing liners without losing alignment, you can align the strip to its intended position on the device, then tape one edge down to hold the strip in place.