Going in with the mindset of not stuttering will only add more pressure and if that doesn't make you stutter more, it will leave you feeling worse about yourself if you do. The best advice I can offer is to allow yourself to stutter, staying as relaxed as possible, and to not let it defeat you if/when you do get stuck. If the other person isn't aware that you stutter, letting them know may help put you at ease. If they do know, and are being rude (such as talking over you), let them know that their behavior isn't acceptable. Even during heated arguments, showing respect for the other person is important! As for actual tips... You could watch YouTube videos of speech pathologists and other people who stutter giving tips and see if one works for you... But the most important thing is self acceptance and not beating yourself up over stuttering.