The late Benedict Hardman in his book, Speech and Oral Reading Techniques for Mass Lectors and Commentators, notes, "The primary cause of fear is thinking of yourself instead of the importance of delivering the material."
Most professional speaking coaches agree that our audience wants us to succeed; that our fellow parishioners are on our side. They come to Mass to hear the word of God; not to judge how good we look or perform. Though there may be an occasional friend, relative or Toastmasters Club fanatic judging us by our speaking skills, it's their loss for paying more attention to the messenger than the message.
We should also know that we're not alone when fear creeps in. Celebrities, politicians, business leaders and professional speakers often get tense before their appearances; not because they're afraid of flubbing, but because they care for their audiences. They see themselves as servants who want to give their listeners nothing but the very best.
Some fear and tension is actually good because it gives us extra energy. If we're too calm, cool and collected at the ambo, we may not have enough "oomph" to move or excite the assembly into savoring God's word.
Hardman cautions, "Beware of being too placid or under-stimulated when reading. If the words on the page merely enter your eyes, by-pass your mind and issue from your mouth, they are usually meaningless."