Super simple responsive email template.
This is a workflow I've been using for a while to create e-mail templates. With gulp, I build the template just as if it was a "normal" website, and then I let Gulp handle the "inlineing" of the CSS.
After you have installed node and gulp. Just run
$ npm install
and then
$ gulp watch
In the src directory, edit the index.html and/or the main.less-file and you will get two versions in the compiled directory. One (index-external.html) with the compiled LESS/CSS file (for use with for example CampaignMonitor, which handles linked css-files automatically) and one version with inlined CSS.
You can put images and other assets pretty much wherever you want, just use relative paths. I find it convenient to put them in the compiled directory. You could of course have them in the src directory, and just let gulp copy them over.
The template that comes along in the src directory is just an example. There are some major issues with Outlook.
You can read more about this gulpfile and template at this blog post (in swedish).