Practice Playing Softly

Playing loudly is the #1 killer of harmonicas. The #1 reason why harmonica players don't employ enough dynamics in their playing is the tendency to play loudly all the time. The #1 tell that someone has not mastered their bending skills is in their tendency to play their bent notes louder than their non-bent notes. The fix?... practice playing every new phrase you learn as softly as possible. Keep the volume of backing tracks low so that you're forced to play softly to hear the track well.