I like at least 1 foot longer than the board but 10 would be fine. Matt is right on about the kinking of leashes wrapped around boards. I have found that you can attach the leash to a door knob as you would to you ankle then lead the leash up over the top of the door and down and under the bottom on the other side of the door with some tension on the leash. Works easier with carpeted floor. In a few days the kinks will pretty much go away.