Use a secure web server to host all images. Images hosted on an unsecured web server run the risk not rendering in the final, deliv ered eblast
Use tables. Email clients live in the past. so all emails must be built using tables for layout. Example: <table>, <tr> and <td>
Use inline styles. Use of external stylesheets is not supported, so to insure your styling is visible use inline styles. Examble: <tr style="paddina-bottom:20px;">
Test your code. Check your code in multiple browsers and in multiple email clients. The same code is not always displayed the same way. Each email client and browser reads your code differently, so do some testing to make sure all users get the same experience when they view your email.
Use text buttons for a "call for action".
Make sure that the HIML code Includes a doctype declaration
Make sure to include the Title HTML tag, with a title that's different from the default one created by many HTML editors (e.g.g 'Untilted' or 'New page').
Alwavs include one or more links. so you can track activity on the message, but try to limit the number of links to 10 or less.
Avoid using special characters. Instead use the HTML equivalent Example: & is the code for '&'
Alwavs open links in a new window by using the target attribute set to _blank. Otherwise you risk having the destination URL open within the current frame of the Web-based email client that the customer may be using, which is not what the customer wants.