Your graphics will come in three layers: a backing paper layer on the bottom to keep the adhesive from being exposed, the vinyl layer (this is your graphic), and a masking layer on top. The masking layer makes the vinyl easier to handle and keeps everything pre-spaced for you to apply your graphic as one piece.
Clean your surface! - Always clean the surface first. No matter how clean it looks, its not worth the risk. Without cleaning, you're really just applying your graphics to dirt, rather than to the actual surface. You can really shorten the durability of your graphics by not cleaning first. light dish soap or alcohol and water will do the trick. DO NOT use cleaners containing ammonia as this will cause the adhesive not to stick. In the case of vehicle graphics, DO NOT wax your vehicle.
Make sure the top of your backing paper and your masking layer are cut even with each other. Use scissors to trim the top of the paper and mask if they are not.
Apply small pieces of masking tape to the top of the graphic - Use two small strips of masking tape, one at each side of the graphic, to hold it in place. These small pieces will allow you to reposition your graphic to exactly where you would like. They work as an extra set of hands allowing you to measure the placement of your graphic to make sure it is perfectly level.
Once your graphic is in place apply one long strip of masking tape across the top of the entire graphic - This step will allow the tape to work as a hinge. You will then be able to lift back the entire graphic without losing your placement on your surface.
Remove the backing paper - Now that your graphic is folded back from your surface, you can peel the backing paper off. Peel slowly to ensure that none of the graphics stick to the paper.
Squeegee the graphics into place - Slowly, starting at the top, in a side-to-side sweeping motion, use your squeegee to press your graphics down into place. Go slow and overlap your previous pass to ensure that you don't miss any spots and get bubbles.
Remove the masking layer - Now that your graphics are applied, you can remove the masking from the top of the graphics. Pull slowly to be sure that none of the graphics come off with the masking. Pulling diagonally across the graphics will help keep them on.
Tips & Warnings
Some surfaces require a little extra preparation ahead of time. Freshly painted surfaces should allow one week to dry before applying graphics. Metal surfaces should be cleaned with a solvent cleaner, such as Prep-Sol, as well as soap and water, before applying graphics.
Temperature can affect your application. It needs to be above 40 degrees F or the adhesive will not stick. Graphics can be applied in very warm conditions, but are more likely to become "stretchy" during application in extreme heat.
On lightly textured surfaces or other surfaces where your graphics want to pull up while you are removing the mask: try lightly wetting the masked side of the graphic using your spray bottle and working it in with your hand. (DO NOT get the backing paper wet.) This will reduce the hold the mask has on the graphic making it easier to separate.
Wet and dry methods - Graphics are typically applied to a dry surface, but for beginners it is common to wet the surface first. Once you complete step 3, you can fold the graphic away from the surface and peel back the backing paper. With a spray bottle, wet both the surface you're applying the graphics to and the exposed graphics. Use water with a small amount of soap. DO NOT get the backing paper wet. With the graphics wet, you now have a chance to lift the graphics back up if you don't like how the application is going. All of the application steps are the same, however you will need to wait until the graphics are dry before removing the masking.