Use real headings
Use the h1 – h6 elements for headings. Using graphics for headings may let you use any typeface you want, but search engines aren’t going to pay much attention. Even if you (as is required) use the alt attribute to specify alternate text for heading images, that text will not be anywhere near as important as real text in a heading element. In my experience, this is true even if the images are inside heading elements. If you know otherwise, please tell. If you cannot use real text, look at the various image or Flash replacement techniques that are available. Be aware that there may be a tiny risk involved in doing so. Since image replacement techniques involve hiding text, it is theoretically possible for search engines to penalise you. Currently that risk seems very slim, but don’t say I didn’t warn you if it does happen.
Use search engine friendly URLs
Avoid dynamically generated URLs that use a query string to let the server know which data to fetch from a database. Search engine robots may have difficulties with this kind of URL – they may stop at the question mark and not even look at the query string. Use search engine friendly, human readable URLs instead. This will help both your ranking and your users. I’ve seen incredible improvements in search engine results from just changing the URL scheme of a site. Modifying and rewriting a site’s URLs can be a little tricky, and some CM systems make it more difficult than others to implement. It is worth the effort though.
Avoid using frames
Be careful with browser detection
If you need to use some kind of browser detection, make sure that it doesn’t break when a search engine spider (or any unknown user agent) comes along. If the spiders can’t get in, you won’t be found. I’ve seen this happen on the sites of fairly large companies.
Don’t waste your time on meta tags
Most search engines don’t place any great deal of value on the contents of meta tags anymore. They have been used way too much by spammers. I’d suggest using the meta description element, but that’s all. Keywords won’t hurt, but they will rarely help either, so they are generally not worth the effort. Some search engines use the contents of the meta description element to describe your site in their search result listings, so if possible, make its contents unique and descriptive for every document.