I am working with an organization that would prefer to have their in-house graphic designer mock up email designs to turn over for me to code. The designer has very little experience with email design and I'm attempting to put together a "best-practices" guide from a design standpoint. I was wondering if anyone might be willing to offer some suggestions as to what I might include or point me to any pre-existing guides that exist. Searching google seems to come up with a lot of information that is either out of date or just flat out wrong; e.g. Background images and web fonts will never render, design for a width of 800px (really?!).