I love Germans.
@HK_Katherine I have to deal with a worse lift situation, in which large groups are needing to get off on every floor. Sometimes it takes over 5 mins to get to the 11/F. I just play Memrise or Quizlet and learn some Chinese characters.
First of all, you need to mentally grapple with the fact that you take the stairs. You are a stairs person. Once you have yourself convinced that you are a stairs person, routinely get into the elevator, press every (or at least half) of the floors, pref. above you if the lift is going up, then excuse yourself and exit saying 'the lift is too full'. Or hopefully the little buzzer will go off giving you an excuse to step out after having pressed 4-5 floors. NB: press the floors discreetly by covering the panel with your body if at all possible.