This exact situation is often a problem for a lot of people, so first off: you are not alone! The absolute best way (in my opinion) to get rid of nervousness before a presentation is to practice. If you are scheduled to hold presentations regularly, then your nerves will definitely disappear after a few presentations. 

For your first presentations though, it's best to practice at home. If you have friends or family that are willing, do the presentation in front of them! This allows you to get a real feel of how it will be to present it, and you are likely to be more confident when the real presentation takes place. 

If you don't have anyone to show it to, do it in front of the mirror! You might feel a bit silly doing this, but trust me, you will still be able to work out the weak spots of the presentation, and also gain some confidence in the presentation itself. 

Other than that, just bite your teeth together and do the presentation. Remember that most people are really nervous the first few times, and it will for sure get better! Good luck.