If you are talking about incoming calls; let it ring a few times, breath in and out slow, deep breaths, and figure out a designated pick up sentence like hello [name] speaking or whatever is comfortable for you. If you are the caller, really think about what you want to say and maybe practice a little bit. And once again, focus on your breathing before you call/engage in the conversation. And remember that you don’t have to hurry. Don’t feel rushed.