Yet another Super Bowl is in the books. The headlines will talk about the Broncos taking home the Lombardi Trophy, the 114 million people that watched the big game at home and how much advertisers shelled out (5 million bucks for a 30-second spot) to catch your attention.

What might not get the same coverage, however, is the huge social media response generated by advertisers. Doritos, especially, knows how to play this social card. For the last ten years, the company has asked its fans to create and submit a commercial that will air during the Super Bowl.

The contest is huge. Thousands of filmmakers apply each year, and millions of fans watch the ads and vote online. Sounds like a pretty successful UGC/social media campaign, right? Here’s what every marketer can learn from Doritos and its notorious Crash the Super Bowl social contest:

Connect a contest to an event

Most contests don’t have a hook. Asking fans to randomly send in a video of themselves using a product isn’t reason enough to participate. The Doritos competition is connected to an event that everyone loves – the Super Bowl.

You don’t have to use the Super Bowl per se, but try connecting your next social contest to a current event or a holiday to increase participation.

Create a buzz on social

Doritos uses social media as a catalyst to advertise the contest, share entries and encourage fans across the world to vote for their favorite.

This year there were 4,500+ entries. Doritos selected the best 50 and asked its audience to narrow the field down to three by voting for their favorite online.

As the field narrowed, Doritos posted individual commercials for fans to check out. Two commercials become quick frontrunners this year: “Doritos Dogs” and “Doritos Ultra Sound.” Each video racked up more than a million views. You can see the ads here.

Superbowl

The takeaway here is to engage fans during the contest. Don’t just ask for submissions on social media, share them and ask fans to comment or vote. Get your target audience involved.

Start early

Doritos started advertising this contest in September. Entries had to be in by the middle of November, and voting took place for weeks.

This requires proper planning. Break out a calendar and figure out when you want to start the competition and when certain messages should be posted.

Have a worthy prize

The Doritos competition has quite a prize – a million dollars. Now, few brands can provide that kind of giveaway, but even without a huge bankroll you can create a worthy prize.

Consider providing an in-store gift card, a cash reward or a popular product that your company makes or sells.

Be sure to advertise the prize and post a picture of the winner on all of your social channels to signal the end of the contest.

The creators of “Doritos Dogs” took home the big prize this year. The company made sure to post a picture of the winners with a check.

Know when to call it quits

If you have a successful contest, it’s likely something you’ll want to repeat. Doritos has held this competition for ten years, but decided that this year was the last.

“Brands have to keep evolving with time. If you look at when we started the program, millennial consumers were the target,” Ram Krishnan, Doritos’ chief marketing officer recently told Fortune Live. “They’ve grown up.”

If you tap into a winning contest, make sure you know when enough is enough. If you continue the contest too long, it will lose its luster.

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