The most important thing a person can do to develop good public speaking skills is to practice as much as possible. Before becoming a polished speaker, one must first gain comfort, experience and poise with the process of presenting in front of a group.
One of the main things to do prior to a speech is to review material and to practice the speech. People get nervous during a speech because they are ill-prepared. When a speaker knows their material, they are better able to speak genuinely, add spontaneous humor and engage the audience conversationally. Preparation includes getting familiar with the audience. Understanding the needs and interests of the audience allows a speaker to tailor the message to his listeners' preferences.
It is important to arrive early and to get familiar with any tools and technology. Setting up a presentation early and knowing the dynamics of a room makes a speaker more comfortable. Start a speech informally; it is okay to even prepare a couple of jokes ahead of time. Throwing in lighthearted humor prepares the audience and helps the speaker get acclimated to the spotlight. Make eye contact with specific members of the audience, and transition from one person to another throughout the presentation. This approach keeps all audience members involved.