[Santa's Helpers]

I have a 8'x20' dark blue enclosed trailer. I want to have all four sides wrapped in vinyl. I have a company that can do it but it is not their main business. They own auto racing teams and bought the equipment to wrap their cars. I need extensive help designing the wraps. I don't have any clue where to start. What program to design it in, what I should include etc. Is there a person or company that can help with the design?
Thanks in advance,
Jeff