Write down your speech clearly on a paper and create reminders and acronyms for phrases you might forget. Go through the speech a couple times until you feel comfortable enough to make the speech without the paper.
Stand in front of a mirror and recite the speech. Work on your stance and your use of hand gestures. When you feel more confident, try reciting the speech in front of someone else to practice eye contact. You can also record yourself, then watch the video to see how well you perform.
Rehearse the speech in the place you will be speaking, if possible. If you have the opportunity to familiarize with the venue, it will give you the chance to find out how loudly you'll need to speak. Alternatively, you can shut your eyes and envision yourself giving the speech in an eloquent and confident manner.
Take slow, deep breaths before the speech. Learn to breathe with your diaphragm to reduce nervousness. If movement is acceptable, take few slow strides and be alert for anything that can make you fall. If movement is not acceptable, focus your attention on the forehead of people in the audience, that way you don't have to look into their eyes and get nervous.
Arrive at the venue at least 30 minutes before your speech so that you can be relaxed. Do not rush your speech but deliver it audibly, clearly and confidently. If you make a mistake, put yourself together, stay collected and continue in a calm manner.