Awareness
- Be aware of what valid [x]HTML is.
- If it's XHTML, it's XML:
- XSLT transformations from it possible
- It won't break XML parsers in cell phones, databases, etc.
- Use a validator.
- If you're using ASP, use a validator on the created [x]HTML.
- Use Tidy
to clean up Tag Soup pages.
- Some authoring tools are starting to incorporate Tidy.