If you really want to be compassionate then giving and taking i.e. if I give this I will get that. Just look at the other person and do whatever he/she needs at that particular moment not what you want to do to feel certain emotions because revving yourself up in certain States of emotions and then acting out of that is not compassion it's a kind of a sickness as in trying to enforce something on someone just for the sake of feeling good. Therefore, in a nutshell, just look at the other person and do whatever he/she needs at that particular moment and NOT what you want to do to feel certain emotions.