I'm a Client Relation Manager aka a glorified Account Manager. I manager relationships with existing accounts at my firm. I grow usage by meeting with senior level people at investment banks, Law firms, PR firms, etc.
If you're not naturally confident which i wasn't, you can always acquire a skill set through experience. I started being horrible at public speaking but now i speak infront of large groups (well) and small groups perfectly.
For me what makes it alot easier is practicing my speech. Although i have a canned speech ready for each type of client i'm visiting which makes it easier, i repeat those canned speeches over and over again. They i think of every relevant question they can ask me and i come up with a good response to it. I practice those as well.
For any question i'm really not sure about, i tell them straight up. "Honestly, i'm not too sure about that. I will get back to you on it." Then i go and take their contact information down and seek the answer and give them a response.
It's the worst to fake an answer both because most of the time you can tell when someone is lying and because you're also lying to a client.
Not sure what the extent of your marketing position entails but my job requires me to make sure our clients understand the benefit of our product and are using it. So i know for a fact that they will benefit from meeting me. I've met with managing directors of investment banks that are at the highest possible position in the firms and are listed on their website. These guys make millions of dollars. The reason anyone accepts to meet with you is because it will be of benefit to them as well.
Remember that business is a two way street. I'm passionate about helping people so i use that to get over my anxiety.
"I ask questions like, what would you like to see in our product?" Then if we have it, i show it to them.
"Well did you know you can actually find that information through xxxx."
"Anything we don't do that you'd like to see? I've actually never heard that before and i'll definitely let our product development team know at our next meeting."
Always practice open ended questions as they will lead to conversation. If I didn't have these questions prepared i would have made a very awkward Account Manager. Luckily i improvise and aim at overcoming my weakness's and now i'm one of the top if not Top performing AM in securing meetings and hopefully renewals (coming up soon).
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Also instead of worrying about becoming a more confident speaker, try to focus on the situation your addressing in your speech and do that well. Confidence comes with being able to do your task well IMHO. When your confident you can help someone, then the speech pertaining to that becomes confident as well.
