I am lucky with my boys, they never do or did bark at me all the time, they are 2.5 years old now! However they did do the nipping thing when they were pups and teething. I gently but firmly used my fingers to close their mouths and made sure they looked me in the eye and them I firmly said "NO BITE!" and they caught on after about a week or two at most. Now they NEVER EVER use their teeth on me or anyone else for that matter!
Good LUCK!!!!