I learned a lot from my friends and my failed presentation.

I learned a lot from my friends and my failed presentation.
For chairing a presentation,
Follow up has priority

For presenting
Present what you have confidence
Present in oral style
Response with "I will think about it, and come back to you shortly", when meet problem.
Be confident

For life
Be prepared for all potential issues
enjoy communicating
Sensitive to other's reaction
Take advices seriously

For language
Listen more
Speak without thinking grammar