Fear of "performing" in public seems to be natural to almost everyone. And there are some good reasons why: the feeling that you're going to make a fool of yourself, the feeling that people will lose respect for you are a couple of examples.
Two keys to success.
1. Focus on your audience and their needs. It is true that you need to have some concerns about yourself in this process, but at the center of your thoughts is a concern for the audience and their needs. Through the entire process of preparation your focus must be on your audience: why should they care about this topic, what do they already know, what do they need to know, what form of presentation will aid them the most in understanding and retaining what you have to say, and what kinds of materials, examples, illustrations, graphics, statistics and other supporting materials will aid them.
It is only natural to be concerned about your personal needs. Will I make mistakes? Of course, but that isn't a problem, you even know what kinds of mistakes you are prone to make. Acknowledge that fact and prepare something that can be said when you make the mistake. Practice saying what you have to say to individuals and small groups so that you and your brain get used to talking about this topic. Know what you're going to wear and then before you stand up to speak, check everything out to be certain that everything that can be done about your appearance has been done and then put yourself out of your mind. Focus on the audience.
2. Focus on your message. Ask yourself why your audience needs to know what you're going to talk to them about. Think of a method that will create interest and a needy feeling for the information you are going to share. Tell them a short story or give them a short example and then move into the main reason you are speaking to them. Be certain that the elements that will be necessary for them to understand and retain are clearly stated and in some memorable form. That would mean you had thought about the best overall way to talk about your topic and noted that in an organizational plan that you can recall and will guide their thinking.
Feel like a missionary. Feel like they will be better off after having heard you than they were before and that they will realize it. Relax, have an enlarged conversation with the individual members of the audience about the topic. Don't be concerned about being perfect in your presentation, instead worry about them taking with them the important message you have for them.
These two items, focus on your audience and focus on your message for them, will carry you a long way toward a successful presentation.