"5.  Be inclusive."  <-- I think this thread could use more of this.  Some things that are etiquette are getting to the point of 'don't do things that hinder my con experience at the expense of your own con experience'

As someone who is both a cosplayer and mother to three small children (6,4 and 2), 
    1. I will try to get to a somewhat out of the way place if someone wants a photo but I'm not going to walk to the designated photo area because that would take way to much time. 
    2. Strollers can be a necessity.  Not only does corralling 3 small children through a con dealer hall require constant vigilance, being able to contain 1-2 children to a stroller at various point makes the outing possible, two of my children wear SMO foot braces.  Their stamina for walking distances is not as high as children of similar ages and they need the stroller to be able to rest in from time to time.  While their braces are visible, most people don't notice them and with the braces my kids walk with a normal gate.  

I think the best etiquette for the con (and life) can be sumed up with the Golden Rule 'Do unto others as you would have them do unto you' instead of a bunch line by line rules that often can't be followed do to various life circumstances.

Just so folks are aware, it is against Indiana state law to smoke within 8 feet of most public places or places of employment, including the ICC.

I kind of have to kick myself for not thinking to put be inclusive in the original post. But We are the most inclusive community I've ever seen.. EVER. Nerd and Geek kind are the most welcoming people that exist. How is it that you can cram over 70,000 into a space like the dealer hall and have people constantly bumping and stumbling into each other, as we all do at some point, and have no major conflict. There are some gatherings of different groups that can't get 1,000 people together without a fight breaking out.
In the end I think we all try to do the right thing. Sometimes we just need a little reminder when we get focused on what we enjoy.

And if you find yourself at your wits end with someone, just challenge them to a game or roll up a character and duke it out that way. :)

Just thought of another one..

DON'T CUSS.  YES there are adults at most tables, but there are also kids around.

Last year I turned from a booth in the exhibit hall and almost got knocked over because someone's four year old was bored and pushed their stroller into me because his parents had looked away for a moment to buy something at the booth next to me. Luckily I didn't step on the kid and the stroller didn't have enough force to do more then make me stumble for a moment, but strollers are just as much of a problem as roller luggage in regards to being an obstacle if you are not willing to be responsible regarding such in a very packed area. Some parents and people who use said roller luggage sadly have a belief everyone else should be looking out for such obstacles and it's not their fault if you are knocked in the shins or accidentally kick one when trying to move through the aisles. It's why I advocate not bringing one in if you don't absolutely need one during that time.

However if you bring a stroller into the exhibit hall it is not safe for your kids or other attendees, you WILL be holding up traffic for everyone around you as you try to shove a stroller down a packed aisle and you WILL be creating an obstacle for everyone going by when you leave that stroller in the aisle- drag it into the cramped booths while you shop. 

You use any kind of "absolutely necessary"  justification because every person clogging up the aisle will use a variation of the same excuse- "my kid can't walk through the exhibit hall without a stroller!".

Part of being a responsible parent is realizing that your kids are not physically and/or emotionally ready for some activities, and that strollers are often not an appropriate solution because it is either unsafe or it will cause problems for everyone else involved. Part of being a responsible parent means that sometimes YOU have to change your vacation plans or what you will be doing on your vacation plans based on what your small children are actually ready for. Part of being a responsible parent means you may have to trade off child care duties, sit out parts of your vacation, or find a sitter. Being a responsible parent sometimes means saying you might have to wait until next year.

The Gen Con exhibit hall is an extremely crowded, over stimulating environment that requires a LOT of walking, and it is packed with people who aren't really paying attention to where they are going let alone their bags/backpacks/luggage/whatever. This is not an environment for strollers.

If we are talking about good etiquette rules at Gen Con creating a problem for everyone around you because it is more convenient for YOU is pretty much textbook BAD ETIQUETTE.

The idea of starting a ban has been brought up in past years  because taking pictures of cosplayers in the aisles is a chronic and obnoxious problem that needs to be addressed. People need to stop taking pictures of cosplayers in the aisle and cosplayers themselves need to tell people that they won't pose for pictures in the aisle. The designated photo ops locations are there for a reason! I don't think any banning cosplay ideas will ever get any serious consideration if people just follow these basic etiquette rules. I have no doubt that a considerate cosplayer like yourself would agree!

When you cram 65K+ people into a relatively small space, there will be conflicts.  You will be bumped into, you will be delayed, your foot will be squished on occasion, you will wait in line for meals.  Accept this.  If you react negatively, this will end up being a major part of your gencon experience and will be the worse for it.  If you smile and move on, say no problem, or chat with the person ahead of you in line, you will forget these things and be happier for it.

So, sure, be nice, be aware of those around you, and be considerate of them.  But when someone whomps you with the backpack of holding, which the will, smile and move on.  It happens.

Finally, as long as the exhibit hall has the Training Grounds which: "This area also includes a space for crawling and newly walking toddlers to run freely without all of the traffic throughout the convention center" you really can't argue that strollers don't belong. GenCon has provided an area specifically for kids of stroller age inside of the hall. 

To reiterate I've always attended alone so really don't have a vested interest in the matter one way or the other, but I'm willing to put up with as many strollers as there are in the exhibit hall if it makes a young parent's life a bit easier and allows them to enjoy the convention. 

Note too that there are side doors leading into the exhibit hall that are right next to the Training Grounds. You do not have to clog up the aisles in the exhibition areas to get to the Training Grounds. You can't use the Training Grounds as an excuse for wandering the exhibit hall.

I would hope that nobody would say that we should exclude people in wheelchairs. Yes, they technically do also hold up traffic but there is a big difference- nobody is choosing to be in a wheelchair, but you are choosing to cause problems in the exhibit hall if you choose to bring a stroller. I would also note that by far most of the people who I have seen using wheelchairs in the exhibit hall have been very aware of their surroundings and will move with and around traffic if they need to- and you never see anyone leaving a wheelchair in the aisle while they shop like people do with strollers. 

I agree with most of the suggestions so far.

+1 Shower AND change clothes daily - You may be nose blind to your smell...I'm not.
+1 Smoke away from doors - I don't want to breathe your second hand smoke.
+1 Be considerate with your strollers - be mindful of others and how you block flow of traffic

+5 Watch out with your oversized heavy bags!!!  I few years ago, when my daughter was 11, some jerk swung his big backpack around and hit my daughter with it.  Didn't notice or didn't care.  My daughter's eyes watered up.  We took a break while she recovered.  Look, you don't have to bring your entire D&D library in your backpack into the dealer hall.  If you really have to cart that much stuff, it is YOUR responsibility to watch for those around you.  DON'T swing it around in a packed hall.  NOT COOL.  I completely disagree with the post that says to just move on when hit with a backpack.  I read this as saying it is OK to bring and hit people with them for the inconsiderate gamers who do.

Overall, my biggest let down is knowing that the people that NEED these suggestions WON'T come here to read them...or worse, read them and disregard them.  I guess the best we can hope is that the few of us who do will do our part. 

What designated stroller area?