I picked this up from another forum called graphics design forum.
As for designing the wrap, I would highly suggest buying the template for the vehicle.
Here is how I used to do it when I did wraps.
Open the template in illustrator, we were using a template a 1/10 scale. I would select the entire graphic, and scale it 166%, this would now give me 1/12 scale, which is an inch to a foot. Next copy the entire graphic, open a new doc in Photoshop at 1200dpi and paste your graphic. Now you have workable panels in photoshop to do your designs. After designing your panels, simply copy them into a new document and add your bleed, it varies from vehicle to vehicle. But anywhere from 4-8" should do the trick. Flatten and print, and leave the rest for the installers.
Getting the images to contour from the sides to the hood, is pretty tricky, I always try to avoid designing anything that would stick me into that guideline. It can be done, but you will need to give boatloads of bleed, and the installers have to be on there game. Good luck!
The entire conversation can be found here:
http://www.graphicdesignforum.com/forum/sh...0473&page=1
Hope it helps.