To improve your public speaking, try the following:
1. Be prepared. Many people freeze up in front of a crowd if they don't have a plan for how they want the speech to go. You must also know your material. Finally, it is important visualize yourself doing well and conveying the main idea of your speech.
2. Be yourself. If you try and script everything, your speech is likely to come across as wooden and might be difficult for others to relate to. Show your personality and connect with others.
3. Don't rush. Pretend you are simply having a conversation with another person. This is the best way to help yourself speak naturally.
4. Make eye contact. Staring at your notes the entire time you are speaking is unlikely to get the audience engaged in what you are saying. Look at the crowd and meet the eyes of those listening to you. Play off of their energy.
5. Use inflection in your tone. This helps to make the material more interesting and can also help you highlight important points.
Infographic credit: http://www.sharonadawson.org/blog/public-speaking-uses-whole-body-infographic/