Apply to the outside of a window or smooth painted surface. It's very important to clean window or surface with rubbing alcohol not windex. Do not apply in direct sunlight, apply in the shade. Do not apply if the tempurature outside is below 50 degrees.
Peel off the white paper backing and apply the sticky part to the glass or surface. Applying from one side to the other will reduce air bubbles. Rub or squeegee on with a plastic squeegee. ( I.D. Cards work too)
Now, Just peel off the remaining plastic or paper application tape very slowly at a sharp angle away from the decal. If the decal starts to come up as well rub it again or squeegee more then try again patiently.
Air bubbles happen. They are a normal part of this type of decal. If you would like you can try to remove them by popping them with a pin and rubbing them, but most will go away on their own. Wrinkles can usually be massaged away with a heat gun.