Do not include profanity or harsh language. 900 numbers can also trigger spam filters. Be sure to use standard formatting in the signature. Navigation It's easy to tell a poor web site from a good one. Just take a minute to look at the navigation.
Poor sites make it difficult for their visitors to find things.
And the more difficult it is for someone to get around on your site, the more likely it is he will leave quickly. You navigation system must be obvious and easy to use. An image-map is great if it is very well designed and loads quickly. You don't want people who have graphics turned off to leave your site. The KISS principle.