With me there are two that I can think of off the top of my head. 
    The first is how tightly my shoes are tied.  I like them tight but not too tight.  I walk forty to forty five miles a week with the dogs so the right feel is important to me.  I don't want to be sidelined by blisters. I've been known to untie and retie a shoe three times prior to a walk and to stop in the middle of a walk to retie a shoe that doesn't feel exactly right. 
     The second is how I wash my fruits and vegetables.  I use a solution of warm water, a little dish soap, and vinegar.  That way I remove insecticides that react to both acids and bases.  And everything gets double rinsed, first in warm water then in cold.  Mom taught me to do that many moons ago.  When I go out to eat or have dinner at someone else's house I'm always a little uneasy because I know they didn't wash their produce as thoroughly as I do. 
    So those are two of my weird compulsions.  Do you have any?