once you are sorted into a house, your username will change into that house's color. that will identify to everyone that you are in that house. Carlisle's House is blue, Esme's House is teal, Edward's House is dark red, Alice's House is royal purple, Rosalie's House is pink, Jasper's House is light blue, Emmett's House is dark yellow, Bella's House is orange, and Jacob's House is black (haha). You will know you have been successfully sorted when your username changes color!