Hayley
What a great question,I have my 9th JY tour booked.
What the tour manager does can actually depend on what sort of tour you are booked on, sometimes very little if I am honest ie Kenya tour as the local somak rep did most of the tour side of things the JY rep was just there for other types of help.
USA tours the rep does get stuck in and can be a great help with places to eat etc, some times they also do a fair chunk of the chatting on the coach drives with information, other times the driver is very good with his knowledge.
The manager gets off and gets the room keys and hands them out and also gives you the information that's needed about meeting in the mornings or evenings with excursion times.
The manager quite often lets you know he/she will be around reception at a given time, for any problems, meal arrangements that sort of thing.
For me the manager is here to make sure I am NOT LOST or missing!!!!...they are very good at letting people find there feet, and just to be in the back ground, and to pick up on things if they occur.
On my tours we have had, lost cases, rooms locked, handbags purses go missing, passport issues, major health issues, tearful people (these holidays can be a time where people can cry and that's fine), scared people, people who are going out of there own comfort zone ie helicopter flights, power boats, Bungy jumps it all happens.
The manager has had to help me with food issues I am a vegetarian, some flights don't have me down there fault not JY so she has had to sort that out...
Most optional tours are paid to the manager and it is there responsibility to sort out transport there and back etc and to let you know the time...
It all does work out really well, so I hope you have a great time.
If there's anything else I can help with just ask
Cindy