Good couple rules to use for searching for those keyword elements are:

1. Use two to four word keyword phrases that people might use to find your website;
2. Search your competitor websites with tools such as a keyword density tool to help identify what they are using.
3. Using the keyword effectiveness index or KEI to help identify how effective your choice in keywords will be is ideal.  The KEI if too high could mean that you are choosing a word that is highly competitive, as well as if you choose one that is too low on KEI then you may not see the effective traffic to make using that particular word useful to you.
4. Avoiding dead words such as “a”, “the”, “but” in your keyword phrases is not advisable and will only break up your phrases into elements that will probably not be as useful as you would like.
5. Utilizing your keywords in not only your content, but your domain name, your links, ‘alt’ tags and in headers, titles and beginning and end of your page will give it strength and credibility with the spiders;

As you can see, it is important to plan a good deal in advance to where your business will come from, the demographic that you need to appeal to as well as your competition in order to start off on the right foot.  Most spiders visit about once a month, and if you plan right and your developer/designer is on their game your keywords, design and presentation of a live site should start  helping your traffic and your ranking with the search engines.  Keyword research and development is important before you start development of your site.