In March 2010, Google had launched the Blogger Template designer as an experimental feature. But today, Blogger Template designer is out from Blogger in draft experiment and is available to everyone.
Blogger Template designer lets you easily customize the design and look of your blog without having to know anything about HTML or CSS. It has a pre-defined selection of templates, images, colors column layouts for you to play around with.
If you log into your blogger account now, you’ll get a notification saying “New! Template Designer” and you can start tinkering with it immediately. Alternatively, you can goto “Design” menu and then select Template Designer. You are free to play around with all the templates, colors, images and so on. When you find your right mix, you can apply it to your new blog or an existing blog.
You can watch the following video, which clearly explains how Blogger Template Designer helps you to create your unique blog design:
(via The Official Google Blog)