Facebook now has 1.44 billion monthly active users and considering the world population is around 7 billion, the numbers indicate 20 percent of the people on the planet use the social network, making it a behemoth of a marketing medium. But running a successful Facebook campaign isn't a slam dunk if you don't know what you're doing. Take some tips from someone who does-Bob Buch, CEO of SocialWire, a recommendation engine for product ads used by companies including Target, Neiman Marcus, QVC, and LivingSocial. Before launching SocialWire two years ago he was VP of business development at Digg where he created DiggAds and helped pioneer the native ad format.

Here's his advice on how to nail a Facebook campaign.

1. Take advantage of Facebook's new product ads platform.

This is the biggest opportunity on Facebook right now. It lets you directly connect your product feed to Facebook and automatically create ads and promote your catalog.

2. Use retargeting.

Unlike the retargeting companies that for years have been marking up the cost of media 30 to 50 percent, Facebook calls its retargeting Dynamic Product Ads (DPA) and gives it away for free. It works by tracking the websites and products people view while browsing the internet and then showing them an ad for those same products when they open Facebook on their desktop or mobile device. This is a huge opportunity for marketers, particularly when it comes to mobile. "Not only is the ROI on mobile retargeting more profitable than desktops, there's much more scale," he says. "You can reach so many more people. And the reason for that is 70 percent of Facebook's traffic is mobile."

3. Create custom audiences.

If you're a brand that knows what your customers have bought from you and you have their email addresses, chances are they're using the same one to access Facebook. This means you can use your customer file to find these people on Facebook and show them ads for the products you know they already like. "That's a much more impacting experience," he says. "People aren't just going through their spam emails. They're engaged, in discovery mode and now seeing a very relevant message."

4. Find new customers with look-alike audiences.

Facebook is able to take a certain segment of a brand's customers-men who buy John Varvatos from Neiman Marcus, for example-and find out what all these people have in common. Maybe they tend to listen to Pearl Jam, or follow LeBron James. The social network can then find millions of users who also like Pearl Jam and LeBron James, clump them together in a look-alike audience and serve them John Varvatos ads. "It is a very effective way for Neiman Marcus to find very relevant, new customers," he says.

5. Employ multi-touch attribution.

For years Google has been giving credit for sales based on an internet user's last click. But what if a person clicks on a Google ad and makes a purchase when earlier in the day he or she clicked on a Facebook ad for the item but didn't buy it because of being at work or for a lack of time? If a brand doesn't understand which ads are truly influencing sales it won't be investing ad spend in the right places and sales will suffer.

To get around this problem, Buch suggests using multi-touch attribution vendors such as Convertro or Adometry, which can give fractional credit for a sale to various channels. "They'll say 'OK, someone clicked on that Facebook ad, and then it was only a few hours later they clicked on the Google ad and bought the thing, so we're actually going to give 80 percent of the credit to Facebook and 20 percent to Google," he says.

6. Perform a Facebook incrementality list test.

It involves showing a certain percentage of a marketer's audience a public service announcement instead of an ad for a pair of jeans. It looks at whether the people who saw the PSA bought the jeans, or whether it was actually a Facebook ad that influenced the purchase.

"A few of the more savvy marketers are just starting to do these tests with Facebook, and what they're discovering is Facebook is delivering a lot more value than they thought and a lot more incrementality, and that retargeters and Google are delivering very little incrementality," he says. "In other words, people would have bought it anyway, even if you didn't spend the money on those retargeting ads or Google ads."