Use catchy images, call to actions and animated gifs that attract attention. Don’t use too many font types, font colours, and font sizes. Let the line spacing be enough. This gives good readability. Depending on the context of your emails its great to use bold colours. Don’t forget to make your email template responsive, so that it looks good across all devices. All in all, designing an attractive email includes minute details and an eye for creativity. It also depends on the type of content and the message you are conveying.