When it comes to writing a list of guidelines or a handbook for the SMs of your university, you will definitely want to get the approval of the staff before distribution. Whether it is the TD, the head of the technical theatre department, or the head of the theatre department, you will save yourself a lot of trouble if someone on staff reads it to ensure that all of the rules you think exist really do exist. There's often quite a bit of bureaucratic red tape associated with universities, and you don't want to get yourself in a legal situation down the line for implementing a set of rules that were never signed off on by someone on staff (not trying to scare you as I don't think it would come to this, but better to be safe than sorry).
Depending on what exactly your advisor is asking you to do, it may be better to set you up as a "mentor" as opposed to an authority figure. You could have a meeting of all of the SMs at the beginning of the semester, and have the TD/SM advisor introduce you as such. This way, you can assist and advise the new SMs and the SMs who have already been in the program won't feel you are encroaching on their style too much. He may even want to acknowledge that the new SMs could talk to the other existing SMs too if you aren't available. In this case, he may want to set you up as the "senior SM mentor" (or something similar).
If there are universal rules/guidelines that all SMs at your university must follow, then the SMs who have already been in the program should follow them too. This is another reason that it will be important to have the guidelines signed off on by a staff member. The SMs could argue with and/or dismiss you, but it becomes harder when it's a department head you're arguing with.
Best of luck to you!!