As a retired teacher I will advise the following:
1. Humor and plenty of it!
2. Realization that each person has their own talent.
3. Help from not only the instructor but each other.
4. Small and manageable size.
5. If beginners very simple blocks.
6. If experienced more challenging blocks.
7. Share triumphs and do-overs.
8. Offer suggestions, not your way only.
9. Encourage fellowship but keep focus on sewing. - Big problem :(
10. Bring snacks to share at breaks, have coffee and tea handy.