the last lot of decals i printed, i pasted them into a word document, and from there clicked on print preview
you can re size the imaje, take note of the size at the top of the window, print in black and white until you get the size right
when you get the size right change settings for colour print.

cheers Ian

added... when you print your test prints do them on normal paper, cut them out and try them in there intended position, then resize and try again if size is incorrect.