the best thing is to practive a little in front of a mirror - make sure you give eye contact but more just to make sure you know they are understanding - look at each person for like 2 seconds then move to the next one. speak slow, take breathes and pause when you need to. It is always nervous when everyone is looking at you and listening, so its almost impossible not to be, but just roll with it. Have your notes but do not stay glued to them. Make sure also you have read over your material well enough to explain it to someone on a one on one. This helps you to have a more smooth delivery since you know the information and are not just reading aloud. If there is someone you know well and feel comfortable with - use then as sounding board to look at for comfort. They will relax you and let them know ahead of time to - the nod of head by a person you know helps a lot to make you relax.