Honestly I sometimes wonder how I did it, because my cats listen to me and rarely do something I don't want them to.
Im firm with them, never loud, never hit them or push them. Consistency might be the key. Always tell them no the same way, as many times as it takes. I'll give them something else to play with if they're ripping something up too.
They're smart, if you spend the time with them.
Someday if you ever live with another person you'll figure it out.