[from article on WebMonkey]
There are three simple, fast, cheap things a developer can do to save time and money

1. Put a document type [DOCTYPE] declaration at the tope of each page, including the link to the standards by which your page should be read. If the DOCTYPE is not there, or isn't formatted properly, the browser reverts to a backwards-compatibility mode, behaving like its quirky late-1990s predecessors
   
2. Validate your code. if you really want to create cross-platform HTML and remove proprietary browser tricks from your site, you should be validating your HTML with the W3C's HTML validator at validator.w3.org Also validate the css and run it through Bobby to test for accessibility issues. WebMonkey has a tutorial on web accessibility.
   
3. Finally: get rid of all FONT tags, and use only style sheets. A core concept behind the development of stylesheets and the document object model (DOM) was the separation of a site's content, presentation, and behavior. Content is to be handled by HTML, presentation by CSS, and behavior by the DOM. .

For some help in using css for layout, check out thenoodleincident.com's tutorial on css box making.

I personally find it invaluable to have a stylesheet editor. I used the free downloadable version of TopStyle for a while, then bought the paid version. It's excellent!

-- posted by Palema on 11/22/2002