Stick	You can play different kinds of sounds using the tip/middle/root of stick.
Hihat	You can play different kinds of sounds by hitting the edge/middle/center of hihat.
Open/Close Shuffle	Hitting right after you opened the hihat, and hitting at the same time you close the hihat. Repeating this action makes shuffle beat. Trying changing the timings of hands and foot and enjoy the different beat.
Open/Close	Open and close hihats by left foot. Hitting opened hihats in the moment. It'll shaper sound when hitting the swaying hihats in different timings. Usually swaying hihats by foot(from heel to knee), but you'll make delicate sounds by ankle.
Adjusting sounds	Adjusting sounds with left foot. Even when stepping on the pedal, you can adjust the level and change sounds. When hitting opened hihat cymbals, you can control the sounds and sustain.
Stepping	2beat, 4 beat in Jazz. It's not just stepping on the pedal but stepping with slightly bend backward. Imagine that oval shape is rolling. Of course, you can step on the pedal with toe.
Counting times	Counting times with left foot. By doing so, you keep precise rythm even without sounds. Being too conscious about metronome rythm or stoic action will spoil groove when they are not proper. It's difficult to decide how many sounds in breaking time or no sounds...
Crashing	You can crash hihats when a left foot release the pedal. It's like sliding the left foot quickly on the pedal.
Mute, etc.	Mute & strong shot, mute & step on the pedal, play on the upper tray, settle a tamboline on the top of axis or on the hihats, rub, touch, shot from the bottom, etc. There are many ways to enjoy hihats.