If I find a spill or something on my shirt like halfway through the day, I try to cover it up so no one can see it even though pretty much everyone already has.

There's one that really defines me...

I'm a band geek, so after my second year of marching (which was in fall) I started having to take four steps everywhere I went, making sure I ended up in certain areas on certain counts. This is very VERY annoying, but I can't get rid of it, and marching band should start in about 3 months again.

I have no idea how to get rid of it D:

For me, if I grind my teeth on the left side twice, I have to do it on the right side twice. I could alternate them, I could go left right left left right right. As long as I hit both sides equally.

Also, if I take a weird breath, I have to hold it in until I count to a certain number. That number changes every time, and I don't know when my next breath will be (I don't have asthma).

If music is playing in a store, I walk to the beat of it. If somebody is walking beside me, I'm always in step with them. If I have to walk for some distance, I have the urge to sing cadences or songs we've played in parades.

Oh my goodness, brethren!

I forgot about those, those go along with what I call the "marching band curse"
Someone told me they even dreamed about marching the show, no joke

I used to have this, if I did something on one side, even moved the foot a little bit, I had to do it on the other side too for "symmetrical balance" or I felt uneasy.

Oh, and I feel forced to do something in beat to whatever I'm listening to all the time. Drumming, grinding my teeth, stomping, sliding - as long as it feels like it's on beat. I usually start drumming in the beat of my walking too. >_>

Oh, I always have to flip light switches I walk by, no matter how bright it is. And I always start out wiping my ass with 3 squares or/and folded 3 times.
I'm pretty sure I have some more, I'll post later when I don't have to run to school.

I do this with everything. If I pick out something to eat I usually have to pick an even number. If I am running on a tredmill or doing free weights I have to stop on an even number of time/kms running or even number of reps within an even number of sets. If I am walking and listening to music I usually try and walk/step to the beat of the song. I always tap my foot to the beat of a song. I have to have all of my songs on iTunes properly indexed e.g. Song title, Artist, Album and Genre.

Oh, man I have so many I keep forgetting...

When I'm eating something that has a lot of small bites involved (popcorn shrimp, candy, ect.) I have to make sure I save the biggest piece for last or I feel disappointed for some random reason.