Designing emails is no easy feat. Unless you know of HTML and CSS, you will find it pretty difficult coming up with a cool looking email design.
However Campaign Monitor is making email design really easy for just about everyone. They have released a new tool called "Canvas" that may just reinvent email design.
Canvas is a email design tool that allows you to choose from a number of available templates and then customise them how you like. You can change colours, text, font size, images and even rearrange stuff by simply dragging and dropping. Each design has also been tailored to be responsive so they look fantastic on tablet or mobile.