As above really, the best way would be to digitally print the colour. Depends on the printer operator but this can take quite a while matching to your paint. You're looking at about 100 quid for materials, little tip for the printer's time, and at least another 100 for fitting. And after all this you'll find your bumper will look totally different to the rest of your car!
The best thing would be a quality respray to be honest. Wraps can look amazing but have to be done in the correct way.
There's always the option of wrapping your entire car!!