How to bring it back to how it was in the beginning

My boyfriend and me had such good communication in the beginning of our relationship, we were able to talk about arguments calmly and the last few weeks things have been rough and blown out of proportion with things that we didn’t mean being said, and both of us miss how we used to act in the beginning. Sometimes I feel it’s too late to just go back to how good we were, but we both have hope in making things work. How do you bring things to calm conversation again? How do you put all the recent fighting behind you and move forward and become better and grow together? how do you break a bad cycle and get back on the right track? :(