If there are more than one marketers coming to the meeting, usually one of them is new and learning, you need to define your roles before the meeting begins.

Role of the new (second) marketer

Introduction

Adequate presentation of the presenter and client so as to create trust and respect on all sides.

Introduction of the presenter - where do you know him from, why do you appreciate him, how successful he is, why you are glad he found the time today ... give him credit

Introduction of the client - why you chose this customer, what is he good at (what is his business), what is the potential, what he has in common with the presenter... (not "I brought him" but "we came here")