Me and mate both think that if we were on it, we would act crazy from the minute we got in the house:
Talk slightly too loudly the whole time.
Grab a knife, sit there mumbling for a few minutes, then slash up a chair and sit down again as if nothing happened.
Always refer to yourself in the third person.
Lob stuff at windows and mirrors.
Set fire to things.
Throw stuff over the walls, like the weeks worth of food.
Sit staring at the mirrors for hours on end.
Walk round nekkid and encourage others to join in.
Wake everyone up at 5 in the morning by pouring water on them.
And then when you leave the house, say nothing during all of the interviews. And then present some obscure satellite show.