Re: one of my cats is peeing and pooping on my clothes....
Welcome, and I'm sorry you are having difficulty with your cats, that has happened to us, too: pee on the bathmats and both pee/poo on laundry on the floor.
Keep the bathroom door CLOSED. (both of us)
Keep dirty clothes OFF THE FLOOR. (husband)
Keep dirty clothes INACCESSIBLE. (both of us ~ hamper with lid)
Keep the cat litter boxes CLEAN and ACCESSIBLE. (litterboxes placed in several quiet areas of the home and give multiple cats several choices of boxes to use)
Another possibility is perhaps some/one of your cats are being bullied away from the litter boxes, or they aren't clean or they don't like the odor/texture of the litter and/or the shape/size of the litterbox.
Also, the number one reason for inappropriate elimination, is some kind of infection that is causing the cat pain or discomfort. A bladder infection or urinary tract infection causes the cat to avoid the litterbox because it HURTS to go there, so they try to find 'softer' places to go, where they hope it won't hurt. If it is a bladder or urinary problem, it will require a vet visit to diagnose and treat with antibiotics, antiinflamatories and/or a diet change, depending on which medical problem it is.
Please do not think your cat(s) are doing this out of petty revenge, they do not think that way. They are trying to tell you something is wrong, and this is the only way they have of letting you know there is a problem.
Good luck with trying to find the base problem and resolving it. Hopefully, more members will chime in with their experiences, too.