When applying security labels there are a couple of aspects to consider in order to achieve the best possible results.
The first recommendation is to always ensure that the surface in which the security labels will be applied is completely clean. Think of it this way, if you apply the label over a dirty surface, the security label is actually sticking to the powder, chemical, or whatever is making that surface dirty, preventing the label to have a successful contact with the real surface that you want for it to deal with.
The next important thing to consider is not touching the back of the security label (the sticky side- where the adhesive is). The security stickers cannot tell the difference between your hand and the surface in which it should be applied, therefore touching the back of it can activate the tamper-evident technology and ruin the label by voiding it prior to it being applied.
In order to apply the security stickers without touching the back of it, it has to be dispensed from the liner by folding it backwards in a rolling kind of motion. Once part of the security label has the adhesive exposed, you want to carefully place it over the surface to be applied - making sure you get the right them in the right place/position the first time. Remember that you will not be able to remove the security label and reapply them. Security stickers would get ruined if tried to remove and reapplied.
Once the security label has been placed on the right place it is safe to wipe it or press it to ensure better adherence and complete contact with the surface.
For the adhesive to cure correctly is always ideal to allow 2 to 24 hours for the security labels on the surface. Within that period it of time the security labels should reach their maximum level of adherence to the surface that they are adhering to.