The Web's Most Effective Ads In the noisy world of digital marketing, these four retargeting channels can bring previous site visitors back to your online store.

Digital advertising is a crowded space, and the modern consumer is constantly pulled in different directions, so it's no surprise that the industry's overall click-through rate hovers at around a mere .06 percent.

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Put another way, that small percentage means that only one in every 1,667 display ads gets clicked. But, don't despair! Targeting people who have previously interacted with your business is more likely to earn you a click, versus targeting those unfamiliar with your brand. And to do that, you should school yourself in the art of retargeting.

While a ton of advanced retargeting strategies are out there to explore, there are four channels online entrepreneurs cannot afford to overlook: display, social media, email and paid search. Let's take a look at each and review the basic steps for starting a campaign.

1. Display retargeting

Simple image or text-based ads populate common banner-placements all over the internet. Typically, they're triggered when you visit a specific webpage that has been coded with a "pixel." So, when you peruse ModCloth.com to find a dress, you will likely see banners for new summer fashions for the next several weeks.

The power of this kind of ad should be self-evident. ModCloth knows that the vast majority of people browsing its dress category has a much higher purchase intent compared to the general population or even the general dress-shopping population. Couple that with brand recognition and good timing, and you've got the perfect conditions for a quick conversion.

Big retailers like Nordstrom and Zappos take this one step further by using dynamic retargeting ads, which employ Flash or HTML5 to feature the exact product(s) a user has previously browsed on the retailer's site.

So, how do you purchase display ads? The Google Display Network (usually purchased through Adwords) is by far the most common platform, since it's easy to use and affordable, compared to larger enterprise solutions. You can also purchase space on real-time bidding platforms. I personally like Simpli.fi.

2. Social retargeting

Social retargeting can be an easy way to reach your shoppers where they spend the majority of their digital lives, but don't be thrown off by changes in language from one platform to another.

For example, Facebook offers a retargeting feature it calls "Custom Audiences." Just drop some tracking code on your site -- or better yet upload your email marketing list --– and Facebook will serve your ads to users already familiar with your brand. It's that simple. With an email, Facebook ads can follow a visitor across different devices. With a pixel, you can serve ads to someone who is using the same computer but hasn't visited your site.

There's no reason to stop at Facebook, of course. YouTube, Twitter and a few other major players have retargeting solutions available to advertisers. Figure out where your audience lives online and focus on the appropriate platforms.

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3. Email retargeting

Email retargeting, like all email marketing, should be a no-brainer. You can start by messaging people who have (or haven't) recently visited your online store. Take it a step further by adding in a behavior your viewers can engage in that's reminiscent of checkout, like stuffing a cart with products or filling out a shipping form, then abandoning the sale.

As long as you've got a user's email address -- via a user login, a site form or a host of user tracking services -- you can set up an automated message a few days afterward to poke people who have left their carts behind.

Sometimes, a simple "Hey, did you mean to do this?" is enough to get a user to return to your site. Otherwise, an offer like "free shipping for a limited time" might be necessary to seal the deal.

4. Paid search retargeting

While paid search is technically just a form of display advertising, it deserves its own section because the application is very different. This channel might be slightly more involved than the first three, but if you're familiar with AdWords, it's an incredible -- and often underutilized -- way to reach potential consumers.

Google's Remarketing Lists In Search Ads (RLSA) allows you to serve text-based ads to Google users who have already visited your site. This may not seem earth-shattering, but the service allows marketers to target search terms that would not be profitable outside of this context.

For example, bidding on all searches of "spring outfits" may not normally be worthwhile for your clothing store. But targeting only the segment of those buyers who have actually visited your website (and may therefore recognize your brand) is much more likely to result in a sale.

Next-level retargeting

Of course, what's been described only scratches the surface of what is possible with retargeting. Various platforms, technologies and more complete data tools provide a broader range of possibilities. If you're looking for more comprehensive help, check out Ripen's downloadable retargeting guide.

But no matter how deep you dive or what path you take, don't overlook the opportunity to put the industry's most effective ads in front of your most likely buyers.

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