I count my steps and they have to end in an odd number.  I have to exhale before entering through doorways, I cannot be inhaling or holding my breath until my body is completely through the doorway.  If I pickup my hands they have to be put down in a different place then where they were before, if any part of the new area is overlapping the old area, then I must do it again...this is a short list of all the ones I've had/have.