I talk to them, I sing to them and I have also been known to have the occasional dance.
The funny thing is that Prema also answers me back. One day Prema and I were having a "private conversation" and I completely forgot that there was someone in the house (not family) who was killing herself laughing because not only did the cat answer me back at regular intervals but also because at one stage I even asked her "sorry what did you say?" I must admit it was rather embarassing