1. Find a Smooth, Flat Surface to Place Your New Sticker
Stickers do not like even slightly rough or textured surfaces. Texture raises areas of the surface and limits the adhesive backing to only the highest points. Greatly reducing the life of the sticker or decal, and possibly damaging the sticker.
2. Thoroughly Clean the Area where You Plan to Add Your New Sticker
Windex or rubbing alcohol works well for cleaning the surface, actually a combination works best. Start by using windex or window cleaner to remove any dirt or debris, let the surface dry, then clean the area with rubbing alcohol. A good quality paper or cotton towel will be fine, but try to avoid terry cloth because it tends to leave lint behind.
3. Consider How You Will Align the Sticker
While the area dries, this is a good opportunity to determine how you will align the sticker. In most applications you can simply use a straightedge on the object to align by. Remember, no one will be measuring to see if you are a fraction of an inch off the straight edge. In most cases making sure the sticker is visually straight is enough.
4. Applying the Sticker
When the area is cleaned and completely dry, remove the backing for the sticker. Put one side of the sticker on the object and slowly move your hand over the sticker applying even pressure until the sticker is completely adhered to the surface.
5. Air Bubbles
Ideally, you should have no air bubbles. If you do have small bubbles, you can usually rub your hand over the bubbles and in some cases remove some or all of them. Unfortunately you are limited on ways to remove air bubbles, avoiding them all together is best. When applying the sticker in step 4 maintaining even pressure as you move across the sticker is the key to avoiding those pesky air bubbles.
(This post will be updated with photos and video soon)