And over and over again. Learn the individual techniques first. Then when you know you'll be presenting, practice them along with the speech. Now, practicing a speech isn't sitting at your computer, reading over your notes. Neither is it just thinking about it.
Real practice means standing in front of mirror, speaking aloud.
Go through the whole thing, and do it many times, until you're comfortable. You can even deliver it to your spouse, family, or friends. You will recognize and tame any anxiety you have about presenting. Without all that fear you find presenting so much easier and better and more rewarding. Then the adrenaline rush you get before you speak will help you instead of holding you back from showing your worth.