What are your best practices for email template design?

Email creative is easily one of the hardest things to design for. While websites only have to take into account a few browsers, there are more email clients than you can shake a stick at. You are on the right path by creating a template that you can re-use.

Here are a few things that I recommend to our clients:
- Avoid using CSS - while most email clients can render it, Gmail does not. It may be repetitive, but using font or span tags usually render on most email clients. Campaign Monitor has a great CSS/Font support chart - http://www.campaignmonitor.com/css/#p
- Use tables for placement of text and images
- Don't use image maps for links -- instead slice your images accordingly and make them links. Some email platforms don't track image map links.
- Always include ALT text in your images
- Use text instead of images with text when you can.
- Be sure to include your primary 'call to action' above the page fold.
- Take a look at your audience. If you can determine which email clients they are using, then you might have an easier time design for them.

Here are other resources you can check out:
- Email Design Review - http://www.emaildesignreview.com/
- Email Experience Council - http://blog.emailexperience.org/