These are our steps on earning a better ROI and a higher CTR for ad campaigns.

Google Shopping is built around Shopping Ads, the small image ads that appear at the top of the Google Search pages. There are between four to eight of these on the search results page and feature the image of the product, the price, about 30 characters of the product’s title, and some optional promotional text.

These images draw the eye and attract clicks. Ecommerce stores that run AdWords Shopping Ad campaigns often bring in their highest ROI through these simple ads. If you’re an ecommerce site owner using Shopping Ads for the first time, you’ll be tickled at how easy it is to upload details of your product stock to AdWords.

1. Create a data feed

If you’re not a technical wizard, you’ll probably want to speak with your webmaster about exporting your product list as a data feed, containing a list of all your products and all the associated relevant information (price, brand, image, availability, etc.). Modern ecommerce platforms make this easy to do with plugins and extensions, so this shouldn’t take so long.

2. Open a Google Merchant Center (GMC) account

Visit http://google.com/merchants to read about this. It’s free. The main purpose is to plug in the data feed from your site. Again, you may prefer to simply arrange for your webmaster to enter your data feed details by giving the login details of your new GMC account. This should be a one-time job. If you set up and install the data feed correctly, it will update automatically as your inventory changes. For best results, set this so that your feed is updated daily. (Google likes fresh data!)

3. Link your Google Merchant Center account to your AdWords account

GMC acts as a kind of middleman, assessing your feed, keeping an eye on the data, and making sure the format is correct. Linking your Merchant Center to your AdWords account is a two-step process. You’ll need to send an approval request from the Merchant Center to your AdWords account. See the Merchant Center help site for more information.

How to get your Google Shopping Campaign up and running

You can now create a new campaign by backing out to your “All online campaigns” view, clicking the blue “+ Campaign” button, and choose the “shopping” option. You’ll see the usual setup options such as “Default bid,” “Daily budget,” “Location,” and so on. Once the setup process is completed, your products will automatically be placed into one product group called “All products.”

However, you shouldn’t activate your campaign and set your ads running because all the items in a group will have the same cost per click, so start by dividing the “All products” group into a set of subgroups. You can have separate bid prices for each. You can create subgroups of products based on any number of attributes those products might share, such as: Category, Brand, Product type, Condition, Item ID. Each of these new subgroups can then be divided into a further set of subgroups based on either the same attribute you just used or a completely different one. Once you’ve finished subdividing, you can customize each subgroup, adjusting the maximum CPC for each one or even excluding particular groups entirely from being advertised.

Warning: once you’ve created your full range of subgroups, your product divisions are set in stone. The only way to adjust them is to delete the product groups and begin again from scratch.

Ensure that your conversion tracking is set up to specify the actual amount of each sale as the value of each conversion. This enables you to set bids for your shopping ads based on profit rather than just the number of items sold. To see this in your AdWords account, add the column called “Conversion Value / Cost.” This is the equivalent of Return on Ad Spend, a valuable metric.

As with most things in AdWords, you’re looking for outliers. Increase what’s performing well; decrease or eliminate what’s performing badly. For your shopping campaign, this means finding individual products that have sold consistently and profitably. You’ll want to increase the bids for these to encourage Google to show them more often. However, don’t be tempted to do huge bid increases at any one time. A “little and often” approach is a better way to go.