I will not sit on my best friend's lap during Transfiguration class, even if my chair has been turned into a cathedral monstrosity and his lap is surprisingly comfortable.

I will not put plaques up where the most memorable pranks of recent history have occurred.

I will not convince unsuspecting purebloods that lampshades are actually very fashionable hats.

I will not give Luna Lovegood a lampshade to wear as a hat.

I will not give Luna Lovegood Ideas, nor will I provide her with a ready supply of Muggle science fiction and fantasy novels.

I will not paint Draco Malfoy's nails pink.

I will not paint Draco Malfoy's nails at all, even if he asked me to do so.

I will not animate scores of stuffed animals and tell students that there is going to be a 'Cuddly Rebellion'.

I will not enchant quills to write what users are thinking instead of what they're supposed to be writing.

I will not install lighthouse lights in any of the Hogwarts towers.