Will your campaign go viral? It's really not up to you.

Take online magazine The Beauty Bean. Like most women's magazines and websites, it offers healthy recipes, makeup tips, and beauty secrets such as "The Best At Home DIY Facial for ALL Skin Types." But unlike most, The Beauty Bean doesn't offer weight loss advice or encourage negative body images for its readers. "It's a place for real beauty, a matter of boosting self-confidence," explains Alexis Wolfer, founder and editor-in-chief.

Though the site gets much of its revenues from ads by cosmetic companies, it has garnered a lot of attention for its Makeup-Free Mondays campaign--a movement to get women to stop using its advertisers' products one day each week. "It was creating a day where we look in the mirror and appreciate our beauty for what it is," Wolfer says. "People refer to putting on their makeup as 'putting on their faces.'" She wanted to remind her readers that they had faces that were beautiful, with or without makeup.

Makeup-Free Mondays took off. A prime spot on AOL for a couple of days gave Beauty Bean millions of unique hits. The story was picked up newspapers abroad and USA Today. Celebrities from Serena Williams to Lady Gaga have posted makeup-free photos of themselves, and though it's been almost two years, the trend shows no signs of fading away.

Here's what Wolfer learned about viral campaigns in the process:

1. You can't create it.

"The best lesson I learned is that I as an individual can't create a viral campaign. That's counter-intuitive," Wolfer says. "The reason Makeup-Free Mondays went viral is that it came from our fans and followers."

At the start, Wolfer and her team were working remotely and, being a start-up, working through weekends. "On Mondays, everyone who wasn't working all weekend is finally emailing you back, so you're super-busy," she explains. Too busy to put on makeup. So she and her team began joking in their social media postings about "Makeup-Free Mondays." "People picked it up and retweeted it, and we thought, 'Maybe there's something there,'" Wolfer recalls.

2. Scare yourself.

Part of the power of Makeup-Free Mondays is that it's frightening, Wolfer says. She kicked off the movement with a blog post accompanied by a picture of herself wearing no makeup that she'd snapped with her iPhone in the bathroom mirror that morning. "I was scared," she says. "I can't tell you how many thousands of dollars I've spent on head shots. You work so hard to create this image, and all my images were very professional. And now, here I am in my bathroom."

It wouldn't have had the same power, she adds, if she'd booked a professional photography session, no matter how makeup-free she'd been. "Creating a viral movement means you have to take on something that you're scared of. People respond with 'Oh my God, I wouldn't have done that!'"

3. Give people something to do.

Wolfer encouraged her readers to take pictures of themselves makeup-free, or even with less makeup than usual, and send them to her. Thousands did. She would purposely schedule meetings on Mondays, ask the women to show up with no makeup, and then ask their permission to take pictures of them when they got there. Most were willing. Part of the fun of Makeup-Free Monday is that it's asking readers to do something fun and possibly scary themselves--not just to pass along a message to all their friends.

4. Give it a larger purpose.

Readers were also encouraged to celebrate Makeup-Free Monday by donating a (fresh) makeup item to a local battered women's shelter. "We acknowledge that a swipe of lipstick can make a women feel more confident," Wolfer says. "And I wanted to include something women could do to give back."

5. Think long-term.

One reason Makeup-Free Mondays is still going strong after two years is that Wolfer still wears no makeup on Mondays, and still posts makeup-free pictures of herself many of those days.

"It's easy to post a ridiculous video on YouTube and get a million hits," she observes. "But that won't have legs."