Well I did my graphics in photoshop, took it into Riccarton Signs on a flash disk, and also had a print out of the graphic to size and trimmed.
Person came out, I showed them how my print out in paper was to fit on the bike tank, they said yeap we have just the thing.
Ended up with nice thick vinyl color for color, and exactly the same as my graphic.
Just stuck it on and clear coated the tank. Bam, done.