Get enough private time and rest before you speak, and after if you feel tired then.
Introvert != shy
Introvert != stage fright
Introvert to me simply means I have a shorter energy supply when around people I don't know.
The closer they are to me, the more I can be around them without getting tired.
So don't equate introversion with social anxiety or inability to speak in public.
So with that said, learning public speaking for introverts should follow the same rules as for anyone else.