Start by brain storming possible search terms. Try to think like a potential customer of your products. What would you be searching for, if your fish needs medication?

Get a few friends or collegues together and ask them. If you already have customers, ask some of them on the phone.

 Write down everything that comes up - at this stage you want ideas, not opinions on the quality of the ideas.

Your brain storming session has resulted in

"fish, sick fish, ill fish, fish medication, fish doctor, fish medicine".

Not a lot, but it is more than enough to get started.

This is because you can expand this short list with the help of the keyword suggestion tools provided by Overture and Google.  

You will find details on these tools on the page  "SEO Tools for web site promotion".

These keyword tools will not only return how often Searchers look for specific search terms, they also suggest other search terms, which might be useful.

Your mission is to analyse the results of these keyword tools to increase your short list, until you can isolate the one or two top performing search phrases, which can attract visitors to your web site.

Finding and integrating these top performers in your e-commerce solution will take some time. But it will be time well spent, if you want your shopping cart software to be busy.

You can only optimize your web site for a small number of search terms. So the better they are, the better your results will be.

Enter all the search terms you have come up with in the keyword tools and carefully study the suggestions.

Sometimes the keyword tools will return better search phrases, which get searched more often. Sometimes you will find a good possible term inside other search terms suggested.

The term "fish" returns a large number of suggestions, but none of them are related to your business. You can therefore ignore them.

But don't ignore suggestions with a low search count during this research stage.

They might contain a gold nugget.

For example the term "ill fish" from the brain storming session turns out to be rarely searched. However among the terms suggested by Google is "ill diseases", which has hardly any searches against it.

That's not surprising, since the term doesn't make any sense. But the word "disease" is certainly worth exploring. So you add the possible search term "fish disease" to the list of search words.

This is where your knowledge comes in. When looking through the suggestions, you have to decide which words could be useful to experiment with. The better you know your field, the easier it is for you to pick up on the useful suggestions.

Only pick suggestions which relate to your field, to ensure these suggestions help you drill down to the best search terms for your website.

The term "fish medication" returns no searches in the Overture keyword tool, but the Google keyword generator returns the term "Fish treatment"  - another avenue to explore. 

The term also triggers an idea:  when people need fish medication, they want to treat or heal fish.

So you add "fish treatment, treat fish, heal fish" to the search phrases to be reviewed.

While you review the search term candidates, you should copy the results from the Overture keyword tool into a spreadsheet program.

Using the Overture keyword tool is more useful for this, as its results tell you how often any given search was performed. 

This is better for sorting the results in a spreadsheet.

The Google keyword tool on the other hand will result in better related search term suggestions, which you can then run in the Overture tool to get an actual number of searches.

I use an Excel spreadsheet, as I can copy the results from the Overture web page directly into Excel, which saves a lot of time.

Once you have the results for all terms in the spredsheet in two columns, you can simply sort the spreadsheet on the column containing the number of searches.

Now you know, which term is most popular.

Here are the top results of our research so far:

Only one search phrase from the original brain storming session has survived among the top five: "Fish".

It's not even a very good phrase for search engine optimization, when you think about it.

It is too broad.

Most people looking for "fish" don't need fish medication. So even if they were to see you in the search results, they wouldn't buy your products. And the ones looking for you might not find you, as they do a more specific search.

The good thing is, that your investigation has brough up another star performer: "fish disease".

A term you hadn't even thought of, when starting out.

That is the power of keyword research. 

Clearly "fish disease" is the term to target for the search engine optimization for your fish pharmacy.