I have been speaking professionally for a number of years now. In a given week, I'm probably speaking 2-4 full days (minus lunch and breaks), teaching various programming languages and technologies. I also give talks at conferences and user group meetings.<p>I remember very, very well when I had to give a talk oh-so-many years ago, while doing a student internship at HP. I flubbed it big time, and left the room saying to myself and anyone who would listen that I disliked public speaking, and was bad at it.<p>I'm not quite sure when things changed, but I think that it had a lot to do with my attitude. Instead of worrying about whether people would like me or believe me, I instead concentrated on trying to teach people something they didn't already know, and have a good time in the process.<p>If I'm enjoying myself while speaking, then the odds are good that the people in the audience are enjoying themselves, too.<p>If I've learned something interesting, then the odds are also good that the people in the audience will find it interesting, too, and will be glad that I'm sharing it with them.<p>Again, I'm not sure when my attitude changed, but when I get up in front of an audience now, I feel like I'm there to have a good time. Of course, I don't want to flub things, and there are times when I worry about that more than others. But for the most part, it's a matter of thinking, "Hey, everyone here has the same goal -- to enjoy themselves and learn something."<p>As others have written, your enjoyment will be enhanced significantly if you prepare. I'd even say to over-prepare. You probably need to know twice as much as you will actually say in your talk, so that you can speak naturally and reasonably about the subject. Try to outline your talk as a story, with a beginning, middle, and end. In technical talks, the story will often be something like, "Here's a problem. Here's a solution. Here are some examples of the solution in use. Here's where the solution fails. Questions?"<p>Don't worry about your slides too much. Yes, they should be high contrast. Yes, they should be easy to read. But I think that people worry way way way too much about colors, fonts, and images, and not enough about the actual SPEAKING. You want people to be engaged with what you're saying, not with what's on your slides... and that's going to happen if you have interesting things to say.<p>Above all, be yourself. There are oh-so-many examples (in real life, and also in movies and on TV) where people are told that they should open with a joke, and so they tell a ridiculous joke that no one finds funny, including the presenter. If you're naturally funny, or are willing to have people not laugh at your jokes, then go for it. If you're a serious kind of person, then be serious. (Although it's always better if you can be somewhat silly, in my book.)