Quoted from sethbenjamin:So…I had to cut this damn thing out with an Xacto knife. Vid has warned us not to do this, and he’s right - you’re going to get a rough edge somewhere that makes the decal hang up and potentially ruin itself on the way off the paper. It’s a major pain and yes, I had to do this twice. Second time laid down smoothly.
Always use a sharp, absolutely fresh blade to cut out a decal, it can help minimize areas of hangups. Most scale modelers do cut their decals, even the factory ones in the kits, to minimize the film. You also cut away from the decal always, even if it means cutting a curve in two pieces.
Quoted from sethbenjamin:One drawback to this is that no home printer I have used ever throws down a really rich black.
If you're capable of doing a direct CMYK print to the printer, use "rich black", which throws around 40% coverage each of Cyan, Magenta and Yellow. It can really help deepen a black. But yeah, most home printers try to make everything look good and get in the way of a professional result.