Whoops, there go my trousers!

I saw a group of one-eyed trouser snakes slithering through the grass.

I put one's trousers on one leg at a time.

I put on my trousers one leg at a time.

He walked into the room trouserless.

She embraced trouserlessness and wore skirts every day.

He walked into the room trousersless.

She wore a stylish trouserette to the party.

She wore a stylish trouserian outfit to the party.

He was wearing a pair of trousersed pants.