If you love cars and have a handful of cool rides that you want to show off to the world, look no further. Driveway car shows are a great idea.

[edit] Steps

Find local car shows. If you don't have the time or money for a car show, look for local car shows around your city and see if they will take your car for the show. Websites of shows usually tell you how to enter.
Look at your driveway. But if you do have the time and money, check if your driveway is big enough. Most driveways are big enough for 2-3 cars. If it isn't though, you might want to stick to step one. You could use your front yard too.
Decide on a date for your show. Saturdays and Sundays are great days. Give yourself at least a few months for planning.
Choose cars. If you already own a classic vehicle, you are in luck. If you don't, you could offer or ask one of your friends or neighbors to display their classic car.
Tune and clean the cars up a bit. That could mean getting a new paint job, installing spoilers, etc. Don't necessarily install performance parts because you don't need those to improve visuals.
Store your show cars somewhere safe. This could be your garage, a car storage area, a highly guarded backyard, a warehouse that you have permission to use, etc.
Set up your cars. Once the day of the show comes, wake up super early and set up your cars. Organize them by maker, kind, color, or random.
Post signs around the neighborhood.
Set up a donation box. Most nice people will give donations.
Hold the show. Greet people. Be cool.
Have an auction. If you want to, hold an auction at the end of the show. Make sure though the minimum price is what you think the car is worth.
The car show ends, smile.

[edit] Tips

Don't charge any money unless you have like 20 cars.
Set up a souvenir shop possibly.

[edit] Warnings

Make sure the neighborhood lets you do this.
Even if you are allowed to do this having 20+ cars can easily block off entire roads. If this occurs your cars will be towed by the city.