My kids helped with the laundry in their teens. I had multiple hampers for sorting, and each one had the directions for that type of load: lights, brights, darks, towels/sheets, work clothes, so no one had any excuse about not knowing how to wash laundry. But they weren't so good at containing things in the bathrooms.
My approach was a little more playful than most of these ideas.
After asking my kids not to leave their laundry on the floor NEXT TO the hamper, I used a post-it note to write "WHY?" With a sad face and tears, on the wall above the pile of laundry on the floor DS didn't really respond. DD asked "why the passive aggressive?" (Uh, maybe because you ignore direct requests?)
So, then, trying not to get myself worked up, and keep it low key, I used a larger piece of paper to create a face for the hamper. Then I added an "I feel so empty inside" thought bubble above it.
That note lived there for a while, and helped more than I would have thought. lol