To be fair they can be quite tricky to start with - splits, ripples, bubbles etc. and then once you've got it absolutely perfectly in place you've to watch and not rub through it with your sandpaper as you layer on (and rub back) your lacquer.
I find that slightly off-cold water rather than warm helps, as it gives you more time to adjust and move it about before it dries on.
The problem with homemade jobs is that unless you have a printer that can do gold or silver they will be naff... they can be a really good way to practice though.