separate the code from GUI thread

Hi, I’m new with threading in qt and I want to know how I can separate a class from main thread and run it on the worker thread? My class is derived from QGraphicsScene and it’s main job is to provide information for GUI like if an item is selected or deleted from the scene. so it is basically a connection between the graphics stuff and my code. GUI and this class are connected via signal and slots connections. Thanks for your help.