What is PR? I guess youre talking about making a template? I think most people are true artisans who recreate holos and just go by eye. Usually it's a state seal that you can create an outline of
I think Shakezula is correct, most people just do it by eye. If it's something incredibly distinctive (a state seal, for instance), you can find something to work from. If it's not, no one will notice if it's not 100% perfect anyway. You can also take a picture of it at the correct angle with a digital camera to get a good idea of what you're shooting for. Obviously you can't trace this directly because the angle is skewed, but it will make a handy reference.