When I first stumbled upon this concept I also decided to try it on a simple task involving human intervention. I intended that my little sister would wipe the dust off my television screen. Imagine a 16-year old girl spontaneously deciding to come do that to an older brother, doing nothing else than that and without saying a word. It took about a week to manifest and I only focused on the intention once. I just sat there with an amusing grin on my face as she left the room.