It really depends on what type of sponsorship your talking about. Sponsorship like a pro shop staff shooter or professional archery shooting for the factory are totally different.
For local staff, you don't have to be the worlds greatest archer. You must portray a positive image, be helpful to others, help people get into the sport or assist those that are already shooter, help out at the local shop when needed, help bring in business, etc.. As a staff shooter, you represent your local shop at all times. Even when your not shooting, you still represent the shop. You do need to be a good shot though and also know your equipment.
Get to know your local shop and see how things go from there.