David:
Zach's procedure is good if you don't have confidence in your ability to attach the vinyl decal level/plumb - or if you are doing production like they are and 'Time is Money'.
I place the door(s) on a horizontal surface and clean the area for the decal with an ammonia-based cleaner first.
Then I use a China Marker to establish the centerline of the door and draw a VERY LIGHT line from above where the decal goes to below.
Now take the decal - with the backing paper still on it - an carefully fold the left and right edges towards each other and just pinch the very top and bottom of the vinyl decal to establish the top and bottom centerline.
Now place the decal (with the backing paper still on it) on the door(s) with the centerline of the decal on the centerline of the door. Once you are happy with the placement 'top to bottom', tape one side of the decal with a long single strip of masking tape to the door, being careful to keep the centerline aligned. Fold the decal back and re-clean the surface of the door to remove any fingerprints and the centerline your drew earlier. Remove the centerline to just above and just below the decal. You still want some line on the door to help you make sure you're 'in line' as you attach the decal.
Now flop the decal over using the tape as a hinge and peel back the release paper from the opposite side of the decal. Peel the release paper back about half-way and cut it off. Holding the edge of the 'open' side off the door with one hand, and using the other hand, slowly start smoothing the decal to the door. Start with the tape edge and work across the part of the decal with the release paper still on it to the part that is 'open'. This way, you are working from the center to the edge of the open portion. Go slow and try not to get any bubbles under the decal as you lightly press it to the door. Once you have gone over the entire open section, go back and firmly work the decal to the door - moving from the center to the edges and working any remaining air out from underneath.
Now remove the masking tape and flop the decal back over the portion that is already attached. Remove the remaining backing paper and repeat the smoothing proceedure from the opposite side - working from the center to the edges.
Large bubbles should not be present when your finished - but if they are, use just the tip of a razor blade/exacto knife to puncture the vinyl at the edge of a bubble and work out the air with your finger. Small bubbles will dissappear in a week or so.
Clean up the rest of the China Marker line and your done!
later . . .
Jim
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