I was shy when I started my career. But you need to take initiatives and any opportunties you can grab to deal with clients face to face. This will help you to improve your communication and dealins with clients and build your reputation and credibility/trust with clients. At the same time, you'll learn the skills of listening by dealing more with clients and to strategically positioning yourself and your services or even referring services which you may not be an expert in but your other team members are (x-sell). Overtime, you'll learn and build yourself in this area. I mean, really, I am of accounting & finance background and like many other majors (eg engineering etc) these subjects don't teach you how to sell...you'll have to get out there, find opportunities to make yoruself known in a positive manner, which often than not, supports your selling skills.