Why not first just set up separate file folders on your PC; it's not like your alters have different bodies that they need whole different PC's? You can even name the folder by each alter's name and maybe even put a "letter" in each to start the dialog? "Welcome" them and tell them what you've done and how much you'd like to hear from them and why? Tell them you're there to help so if they have any problems or questions to let you know?