Take Your Pants For a Walk Day is celebrated on July 27. There are no references to this holiday on government sites and no one seems to know when it all started, or whether there was any significance to the choice of date. Yet it's widely accepted across the Internet as an established tradition.
There are two distinct camps in its interpretation. First there are people, mostly younger and on YouTube, who take the instruction literally and take a spare pair of pants for a walk on a leash or to the park. Then there are folks who see it as an exhortation to get out in the fresh air while wearing pants and get some exercise.
Take your pants for a walk in the park
Whether you choose to wear your pants while walking or take them along as an accessory is entirely up to you. Either way, a walk in the local park or in an open space away from traffic fumes is a healthier choice than a stroll around the city. If you do decide to either trail your pants behind you or sling them over your shoulder, you should probably expect some funny looks and questions, but you'll be doing your bit to raise awareness. If you would rather keep your observation of the day to yourself, keeping your pants on and going for a ramble is unlikely to raise any eyebrows.
Combine your walking day activities
July 27 is also Take Your House Plants for a Walk Day and National Walk on Stilts Day. It's possible that Take Your Pants for a Walk Day is a play on Take Your House Plants for a Walk Day, originally publicized in Chase's Calendar of Events 2000 and copyrighted by Ruth & Thomas Roy of Wellcat.com. National Walk on Stilts Day, while not officially recognized, is a much older tradition. It's practiced not only in the United States but in Spain, the Netherlands and Belgium, though not necessarily on the same day. So why not go for a walk in your pants with a house plant or two, or try a bit of stilt walking? It's probably not a great idea to combine all three, unless you're well-practiced with the stilts.