If you use clear decal film on a black background, it will probably be very difficult to see the decal. The colors just don\'t show up well.
If I have to put a custom decal on a dark background color, I use white decal paper. I print a border the same color as the background color (or as close as I can get) around the symbol/insignia/whatever. Trim the decal as close as possible, apply it, and touch up the border with the background paint.
A few extra steps, but I hope I explained well.
I also have a lot of problems with decals I print wrinkling up, sticking to themselves, ripping, and being ruined. I\'ve discovered that if after I print them I give them a light coat of gloss lacquer and cut them out after that dries, I have fewer problems. It\'s easy to get too thick a layer of lacquer, though , and then the edges of the decal film are very easy to see when applied.
I hope some of this is helpful.
