I always click my fingers and toes, like, all the time
When someone wishes luck, I say "no thanks" because my friend from Poland told me they believe it brings bad luck when I was 13 and I got used to it
Also, when I sneeze or someone else sneezes, if nobody says "bless you" I say "bless you thank you you're welcome"

*I tap my toes to the beat every time I listen to a song. My mom and dad scolds me when I do that.

*I doodle (not like artistic doodle, just random words and shapes). The reason why I always run out of paper. XD

*I use "flop", "ugh", "duh" too much. Pretty much my vocabulary

*I swirl my hair around my fingers.

*I mimic sounds.

...etc.

I "chew" juice while drinking it especially through a straw

biting my lip

Procrastinating. I'm a pro at it.

Procrastinating.
Clicking a pen if I'm holding one.