If I'm going to do anything in the bathroom (use the toilet, brush my teeth, brush my hair, wash my face, etc) I have to first check that the closet is empty, check that the shower is empty, and then check to make sure the door is locked by jiggling the doorknob at least three times. Sometimes I also have to check if there is anything hidden in the cabinets, but that's not very often, and mostly only late at night. I always have to walk with the grain of a wood floor, or the direction of a tile floor. If I absolutely have to walk against it, my steps have to be in multiples of three, and I can't look at the ground while I'm doing it. I've gotten pretty good at a diagonal walk with my feet facing forward, though; I just start turning off sooner than most people.
With food, depending on the food I have all sorts of different ways I have to eat it. For example, if it's something small, it has to be lined up around the perimeter of my plate with one in the middle, and heated up that way. Then I pick which one looks the most delicious, and eat from the opposite side, eating one from each side so that the two sides are even. The one in the middle is eaten after the two to its sides are eaten. There are a lot of other rules, but I really doubt that anyone wants to learn that much about how I eat.