PopClips are designed for 1 time adhesion so chose your area wisely.
Wipe down the adhesion area with a little rubbing alcohol and let it dry.
Peel back the protective sheet from the 3M VHB pad but don't touch it!
Place you PopClip firmly to the adhesion area and leave it to rest for 8 hours. Leaving it will allow the 3M to adhere strongly to the surface so it will work better.
There's an extra 3M VHB sticker with your packaging in case you want to change the location of your PopClip.