In an effort to reduce junk mail, is it appropriate to put RTS on the envelope and leave it for the mailman? Or is that a nuisance for the post office, and something that is not recommended?

I live at a rental and continually get mail that is not for me, but still is the correct address. What should I do with the mail? Do I have to take it to the post office or can I write return to sender and they’ll mail it back for me?