1	Print many multiples - that way if you tear one or mess one up, just cut out another.
2	After printing the decals - coat the decals with Microscale CLEAR DECAL FILM - this will seal the colors and prevent flaking, chipping, running, etc..
3	For smooth surfaces, wet surface with Microscale DECAL SET - this will form a great bond.
4	For irregular surfaces, wet surface with Microscale DECAL SOL - this will soften the decal and allow it to conform to the surface - do not use to much - the decal will become VERY soft.
5	Applying Colored Decals printed on CLEAR Decal paper to white jerseys is MUCH easier than applying decals to dark colored jerseys, since you can just put the decal on as is.
6	If you choose to do dark jerseys you run into some small hurdles. For example there are two popular methods of doing dark jerseys.
7	Make the decal clear. Paint a white block on the jersey or helmet. Place the decal on the block. Trim it out again with the dark color. (sometimes pretty tedious) (click for larger version)
8	Make the decal on white paper. Cut it out as close as possible. Apply to the figure. Trim it out with the dark color. (less tedious painting but more tedious cutting)
9	I prefer to match the background of the decal to the jersey color, apply the decal and then PAINT the jersey color around to decal to blend.