I'm in a love/hate relationship with the convention I'm at because some big things just aren't right. Here's a quick rundown of things you have to do to not torture everyone else at a convention.
#1: Shower
No, seriously. Shower. You are packed on the floor like sardines and you're going to subject everyone else to your aroma? Not cool. A shower everyday plus deodorant goes a long way.
#2: Follow the Rules
Another one that should be obvious yet never is for some reason. No, you cannot cut the line at a panel even with a press pass unless the convention has reserved seating for you. No, being told no heavy metal on the floor does not mean you can use an actual wrench or cast iron skillet as a cosplay prop. I'm at the point that I'll report you immediately just to see you play stupid and try to wriggle out of the rules.
#3: Use Your References
You got your badge and you were handed a map and a program guide. Use them. It's not my job to tell you where the panel room is or when so and so is signing. I'm nice enough to look it up for you because you're bothering everyone else by asking really dumb questions. Reading is fundamental at a convention.
#4: Be Reasonable
This one is more for convention staff, chairs, and volunteers. If you book a venue that has no seating, don't make up a rule the day of the convention that people can't sit on the floor against the wall in a dead area of the convention center. That's just cruel. I'm pretty sure the rule they were told to follow today was no blocking the paths by sitting down, but half the volunteers were telling everybody to stand up no matter what.
#5: Show Up For Your Panel
This is another no-brainer. If you book a panel at a convention and you're in the building, show up. Emergencies are one thing; flaking out is another. Traffic is not an excuse, either. You should always give yourself a buffer when you have to perform for people.
#5A: Actually Announce Changes
The first corollary to #5 is for con staff. If a panel is cancelled, delayed, moved, shifted, flipped, whatever, you have to let the attendees know. It is not fair to tell the person running a panel to let everyone who walks in know that the panel they showed up for isn't happening when the schedule says. You have paper and masking tape. Make a sign with the changes. Have the changes at the information booth. It's not rocket science.
#5B: Don't Fight Over It
Attendees, wake up. This one's for you. I would think people going to a convention wouldn't start a shouting match or get physical with the volunteers if a panel room shifts around, but it happens. Keep your cool. Find out where the panel you want to go to is and head on your merry way. Do you really want to be ejected because you couldn't adapt to scheduling changes?
#6: Don't Be A Cosplay Barnacle
A booth barnacle is someone who just won't leave a booth, asking a million questions or just standing there. A cosplay barnacle bogarts the cosplayer's time under the guise of asking a question or taking a picture. This also applies to press who turn every quick candid into a five minute photo shoot. It's not fair to the cosplayer or anyone else who wants to compliment them or ask for a photo.
It really comes down to using common sense and soap. For the love of everything you hold dear, please use soap every day. Please?