1. Give clear directions.
2. Do what you said you were going to do.
3. Take the time to do the exercise right.

You're probably all, "Dude, duh." Well, try putting them into practice, my clever and haughty friends.

Tell the students exactly what you want them to do, and how they should do it; you don't need to explain why they have to do it that way. The institution of musicianship is not a Pauline Oliveros musical democracy: you are their benevolent autocrat.*

Once you start, try to avoid doubling back. For efficiency and morale, it's better to start with simple exercises that everyone can do and work your way up, rather than aiming high and having to scale back.

Don't settle for half-assed performances. If the students are being bitchy or lame, switching exercises out of embarrassment or frustration probably won't make a difference. Do the best you can to lighten the mood, ask for their support, patience, and focus, and trudge bravely forward.

---Ness

*Unless the exercise is specifically designed to give them a taste of such communal musical delights.