Engrain the curiosity into customers to open your mail and actually read it by displaying special offers, an event details etc.
Keep single message in email that is loud and clear. By having too many areas of focus, your reader is going to get confused about email-content.
Start with important stuffs and get to the point quickly to grab the attent of reader.
Use header and bullet points in your email design to emphasize your content. Use keywords, short paragraphs and avoid lengthy content.
Link every keyword and make it clickable, so that the customer is redirected to product page or website containing information.
Use design elements like boxes, pop-ups, arrows, highlights to grab the customers attention.
Adjust the width to 600px to make sure all the contents appear on screen without letting customer scroll side-to-side on their device.
Use proper text-font format, bold & italics, sub headers etc to make tour email look visually impactful.
As many people read emails on phone, grab every opportunity by optimizing your email to work on mobile along with desktops.
14px to 16px font size is a good rule of thumb for an email to look uniform and professional.
Do not overload your content by using more than two type of fonts. One font for your headlines and another for the content body.
colors are the first thing that catches an eye, add two to three color section on your email. Separate the header and footer by using different colors for more clearance.
Use whitespaces to prioritize your content and make it look more spacious, uncluttered and enhancing readability.