How can I get my mare to stop rubbing me with her face?

I just brought her home yesterday(Shes my first horse, I love her <3), but her owner warned me about this already. She always rubs and pushes me with her head. Apparently her owner before the last one would always let her do it with a bridle on and now she won't stop. What can I do to stop her from doing this? Sometimes it hurts when she does it, I don't want her to do it with a bridle on and whack my face with a bit! The last owner said whack her on the nose and say 'no'. Is that the right thing to do? Thanks!