Taking a plain glass door and making it something special as you would window lettering. Especially where space is at a premium. In this case the gymnastics coach requested that the door be opaque. The same task could also have been accomplished using a perforated translucent materials. When using a translucent material, the look of full color on one side and a tint on the other is achieved. A great idea when an exterior door is involved. There is no size limitation and the durability of the material is exceptional.
The door should make a statement. In this case it is a team message, but it could have been a logo, tag line, or a simple photograph which is enlarged.
Treat the door as if it was a blank canvas and do something special.