This is a simplified version of a traditional Japanese braiding technique called Kumihimo. If you're more interested in the maths behind the numbers of strings and 'spaces moved' that will and won't work, here's a blog post in which mathematician Matthew Scroggs explores the topic a little.
About Katie Steckles
Katie Steckles is a mathematician based in Manchester, who gives talks and workshops and writes about mathematics. She finished her PhD in 2011, and since then has talked about maths at universities, schools events, festivals, on BBC radio and TV, in books and on the internet.