Just for future reference, I got this stuff (£3 at time of purchase!): http://www.amazon.co.uk/gp/product/B000KH9UHM/ref=oh_details_o04_s00_i00?ie=UTF8&psc=1
Quite impressed - that pic above is from when I first put it on but it has since blended into to itself a bit. You just need to make sure everything is clean before you put it on and then it adheres to itself really well without being at all gooey.