I remember when I was wearing a sun dress like 3 or 4 years ago...and that happened on th beach...well luckily it was on the beach so...I was like OH FU?CK! then...some peole laughed..and I took the sun dress off.
It depends on the kind of underwear I'm wearing. If I'm wearing something revealing, I'll quickly pull it down. If I'm wearing less revealing underwear, I just let it drop back down naturally once the wind has passed. I dunno, I don't really get embarrassed too easily.
This has happened to me before a couple times and I just pull it back down then look around to see who my audience is. If it's a lot of people I might turn red, usually though I just keep on doing whatever I was doing.
Neither of these answers. I don't wear stuff like that, but if I did I would quickly smooth it down, WITHOUT squealing and avoiding looking too embarrassed. Why would I want to draw attention to myself?