A's: This is a great question to ask if you are looking to make the tournament run quicker and better for you and for everyone, not just your own team. First thought: Adding players into the system takes time and effort. So to do this the day of the tournament is undesirable since there isn't much extra time. However, if a player is already entered into the system is a no-show, it's very quick and easy to drop them in that tournament that day.
So now to answer your question. The POTENTIAL PLAYERS LIST is a list of anyone & everyone who might possibly show up the day of your tournament from your school. We put all these players into the system ahead of time. We check for spelling of names, grade level and double check everyone is entered correctly. We do ask that this list is in STRENGTH ORDER. In short, it's a list of everyone in your chess program that you submit several days (or weeks!) before a tournament.
Your ROSTER is your line up the day of the meet. It includes who is playing on your team, and what extra players you will have play in the open. Your ROSTER can really only be made the day of the tournament, since that's when you know with great certainty who is actually playing for your team that day.
So you submit a digital POTENTIAL PLAYERS LIST days or weeks before the tournament. And the ROSTER in only made the day of the tournament.
Usually the Tournament Director or Tournament Manager will provide you your POTENTIAL PLAYERS LIST on paper when you check in at a tournament.
During check in your cross out names of players who aren't there.
If you have to switch your STRENGTH ORDER right before the tournament, you can do that. Just use arrows on the paper to show who is going where, and have a quick conversation with the Tournament Director while doing this.
You also declare who is in the Open section.
And now you have made a ROSTER! Congrats! Your team is now ready to compete!
Follow up Q: "But I don't know my final ROSTER that many days before the tournament!"
A: That's true. But you should know who is on your team. So just tell us who is on your team...by submitting a POTENTIAL PLAYERS LIST instead of an incomplete guess at your Roster. This is usually done by Google Form or via email to the Tournament Director and/or Tournament Manager.
PRO TIP: Your POTENTIAL PLAYERS LIST will get used over and over at various tournaments, so once you create it at the start of a season, you only need to update it as you add players as your team grows. So keep a saved POTENTIAL PLAYERS LIST so you can easily find it to enter future tournaments.
Follow up Q: "Is this why you don't allow teams to sign up the morning of a tournament and just walk in?"
A: Yes! That's big reason. The other is so we know how many tables and chairs to provide. And preparing concessions and coaches meal. And to make sure there is adequate parking. And to make sure we have enough materials like notation sheets, pencils and awards.
Example POTENTIAL PLAYERS LIST (aka "not a Roster") that was complete many days prior to a tournament.
Example ROSTER made from a POTENTIAL PLAYERS LIST the morning of a tournament.
A's: Yes! We have an "Air Glenbard" network. Open a browswer on your device after selecting that network. A prompt should appear giving you further instructions. This works for about 95% of chess coaches, and I personally have the most success on a laptop although phones should work too.
A's: Almost always, yes. Though please encourage your players to take only one pencil each per tournament as recently published research indicates a single pencil can be used for more than one round of a chess tournament.