If you have someone who knows what they're doing, do it yourself. If you'd like to do it yourself but don't have someone, take a class or do a ton of reading and watch tutorial videos and try it out on your own vehicles first until you're comfortable with doing it. If that sounds like too much time & work to invest, sub-contract it out. Whatever you decide, just don't go trying to install for a client if you don't know what you're doing. I've never installed myself but I have a few friends who have, and I'm sure anyone that does installs will agree, mistakes are easy to make if you're not experienced and the bigger the wrap the more expensive each mistake becomes.