Being nerdy, doing nerdy things. Pretty much acting like a school tryhard. Of course you can replace the name with anything.
"OMG did you see that?"
"The same poster twice in a row, that's soooo redundant!"
"Dude, you need to stop Pulling a Molly.
Tripping, falling, clumisness, pretty much acting like the earth is tilted and you can't walk in a straight line.
"OMG THAT GIRL JUST TRIPPED ON A BACKPACK!"
"She's totes Pulling a Luisa"