http://cgi.linkclub.or.jp/~null/unicorn/unicorn0.html

Thanks to the instructions in this site, you can emulate Gaff and leave the same origami unicorn he left Deckard in front of your suspected replicant friends´door. This origami unicorn has an intermediate level of difficulty, but the instructions come both in origami signs and pictures for every step, which makes it a recommended model not only for the film fans but also for anyone who wants to understand origami signs better, since you can easily see how the drawings correspond to the real foldings. Good luck and happy sheepy dreams!