study room acoustics
Room acoustics is very important. If your desk/monitors are placed against a wall (or in a corner), bass will reverberate and sound especially loud.
But yes, to "learn your monitors" requires you to know what your mix sounds like on YOUR monitors vs. how they sound elsewhere (car speakers, club systems, laptop speakers, earbuds, etc.). Once you have evaluated a lot of your mixes on these different mediums, you'll be able to know your monitors (e.g. "I know I need to tone the bass down on my monitors to get a good mix" or "each time I listen to my mix on other speakers, my mix is too thin, etc.")