I'd advise rotating sites as often as possible.  I generally recommend someone putting 2 squirts on the inside bicep/elbow of each arm and 1 on each intercostal for 3 days.  Then the next three days switching it up to the backs of the knee and shoulder area.  This will minimize any drying effect it may have.  One+ is an excellent value.  I have more feedback from users who did ONE and 4Aderm (which is the same thing).  I guess people feel that can dose it out more correctly than someone else.