All you have to do is go to Swift Carbon's competition page on Facebook and vote for your favourite frame. You've got a choice of three: the Swift Carbon Detritivore, a lightweight carbon hardtail; the Swift Carbon Neurogen, a super slippery time trial frame; and the Swift Carbon Ultravox Ti, a light high performance carbon road frame.
The frame with the most votes will be given to one lucky winner who will be chosen at random after the closing date of 28 January. The competition is restricted to one entry per person and you have to be 18 or over, but it is available to anyone worldwide. See the full terms and conditions here.