Interviewers

Do they
Start by creating a relaxed and friendly atmosphere so the applicant is comfortable.
Have a list of questions ready to make the interview process fair to all job candidates.
Allow time for the applicant to fully answer the questions.
Begin your interview with open questions that will encourage you to talk, these questions begin with who, what, when, where, why, how.
Ask behavior-based questions, like how you handled a problem in the past.
Take notes and explain this process before you start .

And avoid
Asking questions to which they already know the answers.
Monopolizing the conversation.
Painting an unrealistic picture of the company.
Interruptions - put phone calls on hold, close the door, etc.
Cutting your interviewing time short