Oh yes, I've given plenty of speeches. Lucky for me, I have the gift of the gab. I took speech class and it was an easy A. It comes naturally to me, but I can give some tips.
1. Do not overquote. Nothing more boring than listening to someone "read" for ten minutes.
2. Keep your notes in bullets. Generally it is best not to "write" your speech if you can help it. By only writing down important points that you want to talk about it forces you to make the speech flow a bit more naturally, and again you won't be "reading" as much.
3. Vary your voice inflection. If you sound like a monotone everyone will fall asleep.
4. Consider your audience. I personally am not going to be worded exactly the same when I give a speech to my classmates as opposed to speeches I've made to the town council or board of education.
5. It's natural to be nervous. As good as I am, I still get nervous as hell before a speech. After a minute or two I reach my comfort zone, but the best thing to do, is channel the nervousness into positive energy.