My first big anime convention, Otakon, has passed and I learned a lot by watching and walking around.
Don't demand a photo from the cosplayers. We all know demanding things works out so well. Asking works very well since cosplayers say yes.
Don't take pictures while they are eating. Seriously, photographers circled around the cosplayers like vultures.
Standing in one spot gives someone a good vantage point for cosplayers passing by.
Even if you do not have a costume, you get caught in photo backwash sometimes.
Costume making is serious business.
Conventions are one place where squealing over your favorite characters is not only expect