I use 'Off' as in get off the furniture or off a person/object.
I use a growling 'ahhhttt' sound if a dog puts their mouth on me and remove attention. No touch, no talk, no eye contact (using Cesar's phrase for lack of a better one) after the corrective tone. I usually only have to do this a few times for the dog to catch on.
If it's really bad and the dog is too aroused, (I have an Aussie who goes from zero to 60 even during clicker training and will start jumping/grabbing/biting). I'll suspend whatever activity we were doing and redirect to a calming activity-like having the dog tethered close to you or on your waist with a bone or toy. I have a long leash attached to my couch for this purpose. :)