Hint: don't send send your online advertising traffic to your homepage.
How do you convert online advertising traffic into customers? The key is a phenomenon of human behavior that only comes into play on the web.

You won't read about this phenomenon in books or articles on general principles of advertising or direct marketing. In fact, traditional advertising professionals and direct marketers often create only so-so online advertising campaigns simply because they've never heard of this phenomenon, even though it's essentially the first law of human web surfing behavior.

How to convert your online advertising traffic into customersReady to find out what that all-important first law of web surfing is? Prepare to be not very amazed. You see, everyone who surfs the web already knows about this phenomenon of human behavior because we all do it--even you.

So here it is, the first law of human web surfing behavior, which you absolutely must take into account when marketing your website: While surfing the web, almost everyone will hit the "back" button if they think there's a chance--even a small chance-- they've come to the wrong web page.

The corollary to this law of web surfing behavior: Anyone who clicks through to your site via an online advertising link needs to know they've arrived at the right place as soon as they get there.

Immediately. Within a second. From a click glance. Without having to read anything. The average human attention span on the web has been measured at eight seconds, and you'll have already lost a few seconds while the page downloaded.

The Key(word) to Converting Advertisement-Clickers into CustomersHow do you make absolutely sure visitors feel like they've arrived in the right place?

Make the title and first heading of your landing page (the page on which a visitor "lands" after clicking on an advertisement) the same as the headline of the advertisement that brought your visitor there. If the landing page links to a banner (image) advertisement, use the same pictures and color scheme as the advertisement.

The landing page absolutely must immediately remind the visitor of the advertisement.

The advertisements, in turn, must flow logically from the keywords they are targeting. Even if your advertisements are appearing on websites rather than search engine results, you need to be thinking in terms of the keywords people are using to search for your product in order to speak the language of your prospective customers.

That's why it is very important both your advertisement and landing page incorporate the target keyword prominently, in headings as well as the page body. That's also why it's so important you don't send your visitors from online advertising to your homepage--it's unlikely you could optimize your homepage for all your possible advertisements. Visitors who arrive via advertising need to land on a special "landing page," or they may crash and leave your site.

Conversions: your advertising campaign's goalBut what happens once visitors land on your site and decide to stay more than ten seconds? It's no use if they just hang around. They need to convert.

Important definition: In online advertising parlance, saying a website visitor "converts," means he or she has taken a desired action toward becoming a customer, either 1) buying something or 2) contacting you for more information, thereby becoming a lead.

The percentage of visitors who convert out of the total number of visitors who arrive at your page is the conversion rate. Your goal is to get this rate as high possible. You do that by finding the right message to display on your landing page, and also by targeting the advertising so you are getting visitors who are most likely to convert.

In order to get your visitors to convert once they arrive, you need to make sure they have a clear path to conversion from the landing page. The simpler the path, the better--a winding road might lose some potential customers. This conversion path could be as simple as a "buy now" button or a contact form, or as complex as a multi-step shopping cart with required registration with required email confirmation to scare away those who are not truly devoted buyers.

Targeting your trafficWhat you show visitors who arrive at your site is only half the equation. The visitors themselves are the other. As with everything in life, you can't convert a sow's ear into a silk purse. In this case, the sow's ear is paid traffic that is not targeted, or is coming from popunders or other forced viewing, or is just plain faked (there is software specifically designed to emulate human visitors so fraudsters can sell the "traffic").

Even in the best of cases, some traffic converts better than others. Generally speaking, visitors who are looking for you are the likeliest to convert, so conversion rates tend to be highest from advertising on search engines. Conversion rates tend to be lower from advertising on websites (so-called "content" or "contextual" advertising).

Conversion rates are lower still on advertising on website popups, and lowest of all on so-called adware (programs that display popups on a user's computer; the people who sell this advertising often label it "targeted traffic"). Sending emails that consist of nothing but your advertisement, even if you've skirted the legal definition of spam, is not worth the bad will and damage to your brand.

Preaching to non-converting online advertising trafficA significant percentage of visitors, maybe a majority, will never just click "buy now." How do you reach them?

Many people simply will never make a purchase without speaking to a salesperson first. For them, provide a convenient contact form, as well as a live chat option--if you can afford the time and expense--your email, and a telephone number. A telephone number is especially important since there are some visitors who will never convert without hearing the voice of someone on your end.

For visitors who are not ready to convert immediately, you should have informational articles, "about us" pages or FAQs ready to help them make up their minds.

For visitors who simply will not be ready to convert today, give a reason to bookmark your page. Good articles. A special offer. A newsletter to sign up for. Free advice.

Just make sure you don't place these alternative non-converting options in too prominent a position, or you'll risk distracting prospective customers. A few paragraphs up from the very bottom of the page is a good place to catch people who are interested in you enough to read the entire page, but still haven't converted. The very bottom of the page should be reserved for a conversion option for all the prospective customers accustomed to scrolling to the bottom of the page to get a quick overview.

After all, if you want your visitors from online advertising traffic to convert into customers, shouldn't you at least make it easy for them?