The issue you are facing is called Low-self  Esteem.

Do like this:

1) Never think 'What other will say about me'? Give a damn shit about what other think about you in presentation.

2) Always be prepared  before presentation.  Take a Lead role in Group Presentation.

3)Be bold like a MAN.

4) Watch Some Actions movies.

I still when I gave first presentation in college, I was shivering like Fking Mouse. Overcoming the fear with practice, now I have to speak  infront of director in my work. It is piece of cake nowdays.