Find the perfect setting. Your bedroom does not equal the perfect setting. An auditorium, boardroom or hotel conference room can be very solid settings.
Dress professionally. You want to instill the sense of professionalism in the minds of auditioning actors and wearing a sweatsuit does not accomplish that goal.
Hire someone to handle the actors as they arrive. This could be a sibling or parent, but someone else needs to serve as the gatekeeper, greeting the actors, ushering them in and informing them of the process.
Shake hands with each new actor. Exhibit some personality. They will be intimidated if you stay seated 50 feet away from them. Intimidation is not a good feeling when you want to act.
Have "sides" or portions of the script readily available for each actor as they enter.
Answer any and all questions regarding the characters or film. You don't need to divulge all plot points, but if they feel extra info will aid their process, oblige them.
Inform them of the followup process before they leave, including when they should expect to hear back.