As a track chair, you are responsible for the smooth running of your
track. What that means, exactly, will vary from one track to another,
but it probably means several of the following things.

(Note that there will probably be a TAC volunteer in each room, and
you can delegate stuff if you need to step out for something. You're
not necessarily tied to the room for the whole week.)

Show up early, leave late. Make sure that attendees know they're in
the right place, and, if they're not, direct them to other rooms. (ie,
you should know the general layout of the venue before each day
starts.)

Introduce speakers.

Give the speaker general instructions, such as

* Your session is 40 minutes long, and you are responsible for leaving
time for Q&A if you want.
* Speak into the microphone. No, your voice is not loud enough without
the microphone. No, it's really not. No, I don't care if you think it
is. The microphone is for the benefit of hearing impaired people like
Rich. Please use the mic.
* You have 10 minutes left.
* You have 5 minutes left.
* Your time is up, stop talking

Ask speakers to repeat the question, when they don't do so.

Ensure that the speaker takes all of their gear, and leaves the
podium, as fast as possible after the session, so that the next
speaker can set up. Ask them to take extended Q&A into the hallway.

Ask attendees to stop talking, whispering, taking phone calls, tapping
their foot on the ground, or being otherwise disruptive.

Report code of coduct violations to the event staff IMMEDIATELY.

Notify event staff immediately if a speaker is no-show.

Pick up trash between sessions. Reset chairs if someone has moved them
around.

Help troubleshoot A/V problems, and summon A/V staff if this takes
more than two minutes. Ideally, speakers will show up several minutes
early to get set up, but, of course, many of them won't.

Check badges. We do not expect you to eject people from the event, but
if folks are in the room without badges, please send a TAC person to
notify event staff, so that we can determine next steps.

I think that's probably everything, and I know it seems like a lot,
but most of it just boils down to being there, and adjusting anything
that's not running smoothly, and keeping event staff informed of
anything that you cannot address yourself.