Put it all in a big box and put it on her bed.
I’m sorry. That’s not helpful. Mostly because I live with my husband, who is pretty good about not re-fucking that which I have unfucked. Try a quick conversation, like, “I don’t know if you’ve noticed, but I’ve been trying to get the mess under control and keep the place clean, so any help you could give in making sure it stays clean [note: you’re not asking for help in the cleaning process, just not making it any worse] would be great.”
In hindsight, 90% of my roommate problems could have been fixed with a two-minute conversation rather than 10 zillion passive-aggressive notes.