There are some important elements to bear in mind when writing an email newsletter for a business.
- Most emails are read then deleted in 6 seconds
- Use the newsletter as a way to drive clicks to your website where they can read more
- Make sure your list is permission-based (i.e. that they have asked to hear from you specifically)
- Be consistent with schedule and topic(s)
Using an email editor with buttons and layout options (the upside down "v" layout for key items then 2- and 3-columns), strong imagery, and relevant information.
Hope this helps.