Although it is my own home I needed to blackout two doors in my darkroom. Here's how: get two dowel sticks and staple the fabric to both one for the top and one for the bottom; place two "L" hooks above the door jam drilling two small holes and using plastic anchors into the wall. Just hang the top dowel on the hooks. When leaving for a new flat remove the anchors and fill the holes with some spackling compound. This has worked in my darkroom for 36 years.

http://www.jeffreyglasser.com/