Practice all what you're going to say, try to have pauses before blocks don't forget to breathe . For me I try to look confident and I try to talk with a rhythm with a gentle voice this help me ( I think because we don't stutter when we whisper or sing), also I let my classmate to talk first this help me to have more time to manage my stress before talking I don't know if it can help you For the mistakes, English is not my first language *