There are no exact guidelines to e-mail design.
Your final product should be a design that’s based upon your branding, the aesthetics you want to present, and your target audience. In addition to this, you’ll also want to consider your goals. Good e-mail design works to direct your customer’s eyes (and mouse) to the information you want them to see, and gets them to answer your call to action.
Good e-mail design makes it as easy as possible for your readers to understand your message quickly. By using GIFS and other animations, you can communicate your message with fewer words.
If you need to design newsletter for your product or service, please do not hesitate to contact me.