It is by no means a secret that, in the past few years, Google has almost monopolized the online advertising industry, which also constitute the main source of income for the Montain View giant.

Clearly, there is a lot of money to be made from Adsense ads, provided that you know how to draw and retain a large amount of visitors to your website. But if attracting visitors and making your site engine friendly is somewhat a science with well-defined rules to follow and relatively certain results, that of strategically placing ads in the right spot to maximize your revenue is really more of an art that takes a lot of time and practise to master.

Choosing the right ad format

Google lets you choose among a wide variety of ad formats, which you can place pretty much anywhere in the layout of your page with a limit of three groups per page. One of the most common is the 'skyscraper' format, which you typically want to place in your sidebar; other widely used formats are the small 125x125 pixels and many other different formats of horizontal banners that you can put in the header or footer of your pages.

According to Phoebe Ho, the "Optimizing Extraordinaire" for the Google AdSense team, the best performing format of all is statistically the so-called "large rectangle", 336x280 pixels in size, and the wider formats generally tend to outperform the narrow and smaller ones.

Color scheme: blending vs contrast

When it comes to choosing the right colors to customize the ads, there are essentially two main schools of thought. The first common solution is bleding the ads with the rest of the site, as to emphasize the fact that they are part of the site content and add value to the site; the second solution goes in the opposite direction and aims at making them as easy to detect as possible.

Note that one of these two "schools of thought" does not necessarily exclude the other, but the two are rather complementary. You can see a good example of how both techniques are being applied effectively on the very same page at the Linux.com homepage: notice how the rotating banners in the header are most of the times in contrast with the bluish background, and how that makes them very easy to notice. On the other hand, the ads at the bottom of the page -- and, from time to time, even those at the top right hand corner -- are easier on the eyes and use the same color scheme as the rest of the site.

How much will I make per click?

While there is no way of directly determining how much you will make from every single click, there is a lot you can do to make sure you will at least tend to display the highest paying ads on your site, especially if you are creating a website from scratch.

In fact, Google provides AdWords clients you with a tool that ends up being extremely useful to AdSense users too. The tool is simply named "Keyword Tool", and can be found at

this address.

Complete the form by writing a few keywords, maybe the ones your site is optimized for, and you will be presented with a list of similar keywords, each with its advertiser competition (which, since AdWords is essentially an auction, is proportional to the click value for that particular keyword) and search volume during the previous month.

As you might have already figured out, a good index for the potential revenue of a keyword is the product of these two factors. Try and experiment new keywords, and you might find out that optimizing for one keyword instead of another could bring you five times as much revenue with very little effort.

Finding the right spot

Finding the right place for your ad is possibly the single most important factor of all: the casual reader might see poorly positioned ads like a webmaster's greedy attempt at making money without regards to content, and if this is the case, you will see your visitors exiting your site as fast as they came in.

Many webmasters will simply place their ads in the sidebar, and this is generally a good solution. Others -- including many highly ranked news sites -- will use them to break an article into smaller chunks: although effective, this technique can be even disappointing for the reader, especially if the 'chunks' are very small and the ads take most of the page.

What you want to look for when deciding where to put your ads is a spot that is highly visible, but that at the same time gives the reader the impression they can easily ignore them to focus on the content if they wish to do so.

Consider for instance using a sidebar with a double column layout, the external one providing the usual navigational links, and the second, internal one containing ads in a narrow skyscraper format: the visitor's eyes will have to cross the ads section twice (back and forth) every time they want to navigate your site, but they will also be able to focus on the content whenever they wish to do so, thus having a better user experience and browsing your site more and more.

Putting it all together

That you believe it or not, by reading this article you already know all you need to know to successfully use AdSense on your site. What you may lack now is time and practise to experiment new solutions and see what works for your site depending on your layout, color scheme, niche, format, and so on.

Try to experiment different solutions for an extended period of time until you find the setup that works best for you, and remember that positioning your ads correctly is a delicate kind of art -- even the tiniest, meaningless particular can have huge repercussions on your results.

You can find out more about optimizing Google ads for your website by reading the "Adsense Webinar". It contains a number of real life examples from AdSense users and many tips from expert web designers and Google employees.