Never build a Flash only website
These are websites built entirely in Flash. They are usually great looking and vibrant but search engines have limited ability to index Flash content as it is embedded inside the Flash file. If you have a Flash only website, create additional HTML pages so that search engines can index those.
Avoid Splash pages
Splash pages are graphic entry pages where often the only text found on them is “Enter”. Search engines tends to give more value to the home page than any other page on your website. Splash pages are a complete waste of the most valuable page in your entire website and it should be removed if you want to “up” your search engine rankings.
Don’t use Frames
This is an extension of HTML that allows several web pages to appear in a single web browser window. These pages are held together with a “Frameset” HTML snippet. Frames creates problems with search engines. If the search engines only indexes one of the pages on the “Frameset”, the rest of the content will not be shown to the visitor that originated from the search engine. Frames should be recoded into normal HTML or better yet, XHTML and CSS.
Website builders
These are online tools where you can create your own website online. They usually don’t allow FTP access. Popular ones include “Websites Tonight”, “Websmartz” and “EZ Generator”. These “website generators” usually includes special purpose websites for Real Estate, Mortgage and Insurance websites. Most of the time you won’t be able to conduct aggressive “on page SEO” with these.
Dynamic URL’s
These are database queries passed in the url and they have a “?” in them. Replace the long query strings with static URL’s. If you want more information regarding this and your website is running on a Apache web server, search Google for the phrase “ModRewrite”. If you replace your long URL’s with static ones you will greatly improve the crawl ability of a large dynamic website.