Giving effective speech is purely an art.
Only a handful people can deliver inspiring speech, other make just people yawn. Well, your words are important in a speech, so you should keep them protected.
Make sure that your words are effective and are not stolen by anyone. Using Folder Lock can help your cause as it will not allow anyone to steal your written speech. Here is the link for that
Other than that, your personality counts for about 50% percent of the effect, you need speak with your heart.
Make sure you look like acting. Make some gestures, make your body speak as body language counts a lot. Dress accordingly. The main thing is your confidence, don't shake it up, drop shoulders and have a light smile on your face. You will rock believe me!