The key element to a really successful presentation, and one often lacking, is enthusiasm. Students especially, whether through nervousnessness or a misplaced sense of “seriousness”, often seem to be more in mourning than in celebration. Now some people more naturally evince enthusiasm than others, but everyone has jumped for joy on some occasion, at some age. Draw upon that experience. Remember how excited you were to make that breakthrough, or to have it accepted for the conference, and don’t be afraid to let these feelings show. You may feel self-conscious, but it is almost impossible to overdue enthusiasm. (Well maybe Steve Ballmer.) How can your audience be interested if you don’t seem to be? On the other hand they will be caught up in and remember your enthusiasm.
Here is a related post, that suggests one specific route to the enthusiastic heart of a presentation: start with the “why”.