Is there a politer way of saying 'don't get you panties in a bunch'? [closed]

Well, there's

"Don't have a cow, man!",

but that might have a similarly negative impact. I use

"Calm down, Charlie Brown!",

which is a reference to the gag from the Peanuts comic strips where Charlie occasionally lost his cool. There's also a derivation (possibly the origination) of "panties in a bunch", which is

"Don't get your knickers in a knot!"

Has a nice ring to it, and might not turn as many heads.

"Take a chill pill!"

is another common one.

Well you could try this expression. It's not humorous per se, but it's been pretty popular lately. For example:

"What! Are you saying you left your wallet at home?"

Note that delivery is key to pulling this off.