Close any windows you may have in your bathroom. Smooth strips of masking tape along the seams of the windows to seal them if the window isn't self-sealing.
Close your bathroom door, with you in the bathroom, and use masking tape to seal the cracks between the door and the door facing. Roll up a towel and place it at the floor against the door to keep air from getting in or escaping.
Turn on your shower, using the hot water only. Let it run to fill the room up with steam.
Scoop some ice out of the pewter bowl with the ladle and dump the ice on the shower floor. The cold will mingle with the hot water, creating thick billowing clouds of steam that will rise up through the bathroom.
Spread two or three drops of essential oil on your shower floor or in the ice to include aromatic hints with your steam shower.