Hi freckles, and welcome to FT!

Don’t worry about your underwire bra setting off the WTMD. I’ve worn one through security several times, along with a bracelet, watch, earrings and toe rings, and I’ve never alarmed. You also shouldn’t be overly concerned about receiving a pat-down search. In the unlikely event you’re selected, just smile as others have suggested. And don’t forget to ask the TSO to put on a new pair of gloves. BTW, some TSAers actually realize how silly the whole thing is, but there’s not much they can do to change the procedure. So just give them a big grin and perhaps even a laugh, especially if you’re ticklish like me.