If they had given you transmit priveleges, they would have told you everything you need to know. Or, they would have just issued you a radio.
I would very seriously reconsider transmitting if you are not properly authorized to do so. You have got to understand that it looks very suspicious that you come on here and ask how to set it up. In other words, it would be very easy to mistake you for a high school kid who just got a radio and wants to interfere with the school buses for whatever reason.
If that is your intention, don't do it.
If you are properly authorized, have their radio shop set it up for you.