Pen + paper. This approach to describing interactivity flows on paper https://vimeo.com/133046716 https://vimeo.com/133046716 Balsamiq Middlemanapp + scss +

Pen + paper. This approach to describing interactivity flows on paper https://vimeo.com/133046716 https://vimeo.com/133046716 Balsamiq Middlemanapp + scss + susy grids one for an html prototype which then becomes the style guide.