How do you write both sides of a telephone conversation in a novel?

Question

In a novel, when there is a telephone conversation and you want the reader to know both sides of that conversation, how do you write that?

Answer 1

Write it like you would a normal dialogue scene.

Don't include gestures, obviously... only include observations of the character you are following... tone of voice of the other person, background noises, pauses.

Answer 2

yes i agree with the first answer. but if its a phone conversation that your main character isnt involved in, you could have it where he/she picks up the phone and listens in.