Let's expand the list!
✿ Doing the tea ceremony with Lipton
✿ Using a shoelace as a string in shamisen
✿ Reading manyoushuu from left to right
✿ Going through the middle of torii
✿ Sleeping with head facing north
✿ Not getting rid of almost century-old things
✿ Killing spiders during daytime
✿ Not killing spiders during nighttime
✿ Drawing ghosts with legs
✿ Following sparks during night travel
✿ Using ink to make soy sauce darker
✿ Tossing 10 yen coins
✿ Spitting water back to the tank after temizu, or drinking it
✿ Always making い and り look too similar in handwriting
✿ Drawing ghosts with fire, but failing to signal them to go back with another fire
✿ Hanging paper ghost not right side up, nor upside down but horizontally
✿ Thinking that Buddha is not among the oldest and most powerful kamis
✿ Not blaming your bad health on a curse cast by a clairvoyant pipe fox servant of the person that doesn't like you

What are other wrong or hilarious-sounding things?