Form an interview committee. Ensure the interview committee contains all the representatives required by your university and departmental procedures. Typically, committees contain the department chair, ex officio, a student representative, an affirmative action representative, one other member of the hiring department and an outside member from another department. If you are doing preliminary interviews at a convention, consider creating a subcommittee of people already giving papers at the convention to act as a special "convention interview" subcommittee in order to save travel money.
Obtain approval for your long short list from your dean and the affirmative action office.
Schedule a list of available interview time slots for all committee members before having your secretary schedule candidates for interviews. During a given interview stage, all candidates must be interviewed by precisely the same committee to avoid violating university and affirmative action procedures.
Prepare a general outline of how you will allocate interview time. Some universities require that all candidates are asked the same questions. Others have more flexible policies. Whatever the specific procedures, ensure to cover teaching, research and service. Teaching questions should address the full range of courses a candidate might be asked to teach.
Allow at least 5 minutes between interviews to write up notes and confer. Especially if you are doing multiple hires, and interviewing 20 or 30 candidates at a convention, it's easy to forget details unless you make careful notes.
Obtain approval from your department, dean and affirmative action office for your short list. In particularly "hot" fields, you might want to have the convention committee pre-authorized to make campus visit offers at the convention. Make sure to have all your paperwork organized and a departmental meeting scheduled as soon as possible after preliminary interviews are completed. You can lose top candidates by moving too slowly.
Decide on whether you want to bring candidates in priority order, only moving to your second candidate if the first doesn't work out, or whether you wish to bring all three to campus before making a decision. Your choice should be based on whether you have a clear standout candidate everyone agrees on, or whether your three top candidates appear fairly even.
Send the candidates detailed information about your program so they can prepare answers to teaching questions. Your local Chamber of Commerce might have good informative packets about the community. Consider arranging an introduction to a real estate agent so that candidates can get a sense of the local housing market.
Make sure to have identical schedules for all candidates. Interview schedules usually include meeting with the hiring committee, a job talk about the candidate's research, a meeting with graduate students, a meeting with the department chair, a meeting with a dean and some sort of meet-and-greet event. For nontenure stream posts, substitute a teaching demonstration for the traditional job talk.
Convene a planning meeting before the campus visits start in which you plan what questions and information will be covered in which part of the visit. You don't want to have the Chair and the hiring committee duplicate questions. With good planning, the interviews themselves will smoothly progress.