Write down how to assemble things! This includes TV stands, bookshelves, bed frames, futons, and anything else that needs to be taken apart and put back together. Once people figure it out the first time, they have a tendency to enjoy the finished product without documenting how the heck they put it together. While it's fresh in your mind, write down instructions or draw a picture and file it away where you'll find it later (or, tape it to the bottom of the furniture itself).
