First things first!
Basically, you are just another salesman. All good sales people are clean cut, well dressed and speak well. You need to have these basics just to be even with the competition. With out these basics, the first impression you create will kill your sales presentation.
A major tip to getting a sponsor for your race car, is to think like a business owner.
Say you own Joe's Auto Parts. From a business stand point why would you want to sponsor a race car. Before you say "visibility," think how much radio and print advertising your parts store could buy for the money you would spend on sponsoring a race car. Just the name of your store on the car will not make people come in and buy parts, but an advertisement on radio or in the newspaper does tend to make people come in and buy parts. Just a rolling billboard is not reason enough to sponsor a race car.
So why sponsor a race car?
It does help if your sponsor's product or business is something the people in the stands would use, but it is not absolutely necessary. If that sounds funny, look at the companies sponsoring Indy cars, you've never heard of half of them or know what they sell. Again, if you are a rolling billboard, the cost of sponsoring a race car is more than the cost of a billboard next to the highway and many more people will come down the highway than sit in the stands.
It is a common misconception among racers that advertising to the people in the stands is good business. No race track has enough seats to justify the cost of sponsoring the type of car racing there, even NASCAR tracks which pull the biggest crowds don't have enough bodies to justify the sponsorship of a Winston Cup team. The track owners and promoters are making the money off of those seats, not the sponsors.
The trick is that you have to do more!
Think of the sponsor as your partner. Think of ways to improve your sponsor's business. In doing things to help your partner's business it will take more money than just for the race car. So, realize you are asking for more money than just the cost of a new engine.
"Unique Visibility" is one aspect of sponsorship, but, go the extra step. Use the race car for more than just a show car at a grand opening or big sale. Paint the race car and your street car/truck exactly the same (right down to the numbers and stickers). Offer to paint the sponsor's delivery vehicles to match. Or go the other way! Paint your vehicle to match the sponsor's and give them the numbers and stickers. This does require that your car live up to the sponsor's image. For example, do you want some old wrinkly beat to hell s--- box representing your business. The race car needs to be clean cut, just as you the salesman need to be sharply dressed.
Now, use this unique visibility! The rolling billboard can be used at more than the race track. It can be used at the sponsors business, or away from the business. Shopping centers, intersections or any place that has good traffic is a target for your billboard, but go the extra step. Have a professionally painted sign saying "Come into sponsorsname and get discount tickets to see the sponsorname race car in action." Or "Come into sponsorname and sign up for a chance to..." or "Come in to sponsorname for this weeks special on ..." or any other idea that will cause people to go to the sponsors business. The race car is an eye catcher so use it to convey a message. By having the extra vehicles painted just like the race car you can get more opportunities at unique visibility. Now, use the unique visibility to get people in the sponsors front door.
The unique visibility can be double played, too. Offer a package deal in the sponsorship that includes prepaid newspaper ads to run when the sponsor wants to run them. Have professional ads done using the car as an eye catcher and run it in the local or regional newspaper. The message in the ad can be the sponsor's choosing or you can do the same message as on the sign placed with the race car. You may be tempted to run this ad the racing program, but that may have a small coverage for the price in comparison to newspapers. So, be careful not to stub your toe on this one! Think about cost per impression, how many people will see the message and at what price.
The possibilities are unlimited once you start thinking how the unique visibility can be use. But, this is not the end it is just the beginning!
What else can you do for your sponsor/partner?
If a company sponsors a softball team it is not for advertising value. Typically, several or all of the team members are company employees. The "team experience" and "morale builder" are the company's reward for sponsoring the team, not the advertising.
Likewise you can establish a similar program with your race team. Provide pit passes or tickets for the grand stands to the sponsor. These items can be used as incentives by the sponsor for the company employees. But don't expect the sponsor to do all of the thinking, remember he is your partner, so help him.
If there is a company problem with absenteeism or tardiness the program could be "any employee that has perfect attendance, and never tardy, gets their name in a drawing for the tickets." If the problem is low productivity the same approach could be used; any employee meeting specific production levels gets tickets or pit passes. You could even have them be part of the team.
Tickets can also be used as customer "Premiums" by the sponsor. "Buy five tanks of gas and get a free ticket to the races." Remember, the eye catching unique visibility gets a potential customer's attention. A message (sign) coaxes the potential customer into the sponsors business. Now, you convert the potential customer into a repeat customer with the (buy this many and get the free ticket) deal.
There is no limit to this approach. Say you were sponsored by a sandwich shop. You could offer to print the sandwich wrappers with the gimmick "Return 10 wrappers for a free ticket to the races." This way the sponsor gets repeat customers and you are providing him with materials he doesn't have to buy. Of course you don't tell him, but that is where you spend some of that extra money you got from the sponsorship. But, you sell this as a double advantage to the sponsor.
The biggest tip is to think like a business person and not like a race fan. Built a package for your sponsor that covers as many aspects as possible. Here you have seen how unique visibility can catch a potential customers attention. Also, how to use that moment to convey a message. You have also seen the concept of creating repeat customers for the sponsor. Any trick to improve productivity, or service within the sponsor's business is also good. If a fan from the race track happens to be converted to a customer it's just a bonus. Using you imagination you can develop a sponsorship package that really works.