You want to do this: Buy and wear plastic Mardi Gras beads.
Do this instead: Buy and wear a hat.
For some reason, visitors to New Orleans feel a soul-deep need to throw on Mardi Gras beads as soon as their plane touches down, regardless of whether or not it’s Carnival season, as though it’s our version of the Hawaiian lei. It’s not. The only time anyone should be wearing beads is if A) it's Mardi Gras, B) you’re at a parade, or C) you’ve caught them in the air yourself (not picked up from the ground, mind you, or paid for them in a shop like a sucker) or bartered for them "the old fashioned way". If you feel the need to buy something to wear for your stay in the Crescent City, make it a great hat. It’s hot down here, so it’s legitimately practical, plus we have some really fantastic artisanal haberdashers like the Goorin Brothers. Also, the ladies love a man in an excellent hat (“It makes you all look like Don Draper on vacation”, says SoBou’s bar chef Abigail Gullo).