Production Scheduler Resource groups & Item Groups

PS Gurus

Years ago a consulting firm got us setup and running PS.  So the setups we have are there and work for PS.  However as I am still playing and learning PS I have attempted to cluster and use resource groups within PS.  I am trying to figure out once I have created a new resource group and added my desired resources to it how do I save it so that it re-appears next time I open a new model?  It is there for the current model but once I come back next day or just open a new model it