Once upon a time, a long long long while ago, someone very generously shared this over at the docrafts forum. I am really sorry, as I can not remember who it was. If it was you, please leave me a message, I will credit you accordingly and link to your blog.
Just been to a demonstration, and one of the topics was bow making. As promised I have posted this picture how to tie a bow using a fork. It has been photographed step by step. Hope it helps.