It depends entirely on the type of toilet.
With an Asian squatter, you're well advised to take your pants off completely and hang them on the nail on the wall to avoid getting them wet in the puddle on the floor.
With a urinal, I generally just pull put my dick (over the waistband) because my underwear lacks a fly. BTW - I now think a fly on underwear is a useless complication - just tuck the waistband below your junk - easy.
With an Asian squatter, you're well advised to take your pants off completely and hang them on the nail on the wall to avoid getting them wet in the puddle on the floor.
With a urinal, I generally just pull put my dick (over the waistband) because my underwear lacks a fly. BTW - I now think a fly on underwear is a useless complication - just tuck the waistband below your junk - easy.