The design and development for email marketing is always very important in order to have the highest delivery, encourage your recipients to click and increase the responsiveness. Also, as the users are increasingly reading their email through their mobile devices, you need to make sure that the creative is mobile responsive.
The creative should have a header, body and footer
HEADER
The header must have a link to a web version of your email creative. In order for users to recognize and trust the email received, it is always good to have the logo of the brand, or the newsletter where they signed up. In this way you make sure they recognize you as the originator of the email.
Some people put the unsubscribed link in the footer; It’s also recommended to put it in the header, as it avoids recipients to hit the spam button before. Think about it, if the user has to scroll down all the creative to be able to reach the unsubscribe button in case they don’t want your emails anymore, most probably will hit the spam first, rather than scrolling down. It is always better to have unsubscribes rather than hitting spam.
FOOTER
In the footer you can include information about the brand or newsletter, like the address, phone number and contact email. There should be also included the unsubscribe link allowing recipients to opt-out.
BODY
The size of the creative should not exceed 700 pixels, so it could fit in different email clients. If it is bigger than this, the user will be forced to scroll to the side in order to reach the content. So you probably want them to have access to your content easily. Also the file sizes you want the email to carry should not be more than 100k to avoid loading time. Remember that the smaller the file, the quicker it will load. It is necessary to have Calls-to-Action (CTA), with phrases like “Click here to…”, to make content and help users make navigation decisions, and guide them where you want them to go through the design. If you are planning to use images, you need to make sure that the relevant content does not appear only in the images, because if it takes times to load you will make the recipient miss the message of your email. Most of the email clients ask for permission to the user in order to show the images, so in case they have not given it, the important message won’t be shown. Don’t forget to add also the “alt” attribute inside the images of your HTML code, in order to show a message in case the image cannot be displayed.
Make sure that the text you include is easy to read, with a readable font and to combine the right color of the text with the background to be able to be readable to all users. Try to choose a text color that gives the highest possible contrast. The minimum font size on the body should be 10 point, and only secondary text like the terms and conditions can be smaller.
Finally, the subject line; this should not be of a length longer than 80 characters, and this is already a bit long. I would recommend making it shorter than 50 characters. The subject line should not include upper case, and should avoid spammy words such as: free, available now, download, discount, win, sign up now, and mainly percentages of any kind.