Back when I was a little punk, I used to be fascinated with the way the pit would move and gyrate at big shows. I found it easer to think of the crowd as a rushing current and treat it as such.
If I wanted to hold my place relative to the rest of the crowd, I’d put my arms around the shoulders of those around me in such a way that I was supporting them as much as I was holding myself up. That way the people around me didn’t get angry or try to shrug me off.
If I wanted to get out of the crowd, I’d turn my body perpendicular to the direction everyone was facing, then just push along the path of least resistance. Or, I’d jump on top of everyone and “swim” to the back on top of the crowd. Don’t try that in a stampede, though, because if you go down head first you’re finished.
If I wanted to hold my position relative to the room and not the crowd, I found there isn’t really any good way to do it except to press my back flat against a wall or place myself in the lee of some sort of object like a monitor or a soundboard.
If I found myself in a situation like one of the disasters we’ve seen this week, the first thing I would do is mark the rear exits and try to get against a wall and out of the crowd rush as quickly as possible. (And pray the rear exits aren’t barred.) I would imagine that the ones who died the quickest were the ones who went for the main exit and got stuck standing up in the smoke.