Origin of a pattern in my blog http://brightbag.blogspot.com/2013/01/lacy-granny-square.... (hand drawn pattern)
It has been hosted in spincushions crochet along week 11 http://spincushions.com/in-a-spin-week-11/ (chart and written instructions in US and UK terms)
And here are the tip for the diagonal color change http://brightbag.blogspot.com/2013/01/diagonal-color-chan...