No business happens until someone sells something. And increasing sales results is often the best answer to any business problem there is.
Being enthusiastic about the opportunity to share ways in which you can help someone else achieve their goals is the critical first step.
After you embrace a wonderful sales mindset, then professionalism at every step in the process (building great relationships, exploring ways you can serve, presenting proposals, asking for the order, handling objections, following up, etc.) is essential to optimal sales success.