Based on the premise that the best predictor of future behavior is past behavior, behavioral interviews aim to find out about a candidate's skills and abilities by asking questions about her past experiences. The ideal answer to a behavior-based interview question highlights how the applicant successfully demonstrated the desired skills and abilities in a prior position or experience. It is difficult to fabricate answers to behavioral questions -- at least not convincingly -- and this is another reason the behavioral interview is popular with employers. Solid preparation is necessary to deliver the best performance at a behavioral interview.
Review the vacancy announcement and job description for the position. Determine the key skills, abilities and qualifications necessary for the role. Create a list of all the key competencies.
Think back to your work experience, achievements and successes. Draft a list of events and situations that highlight a critical ability or skill you possess.
Match each incident to one or more of the key competencies of the job. Some achievements will naturally lend themselves to multiple competencies. For example, the completion of a complex project with multiple stages might demonstrate prioritization, organization, teamwork, multitasking and meeting deadlines.
Reduce your answers down to the key points you need to convey. Identify the aspects of the story that demonstrate your abilities and focus on explaining them in a concise and coherent manner. Skip the finer details and try to keep the story to no more than a minute or two in total.
Practice your behavioral answers with a friend or trusted colleague. Rehearse your stories until you are comfortable remembering each detail and how it intersects with the key skills required from the ideal candidate. Practice recounting the story to demonstrate each of the different competencies.
Preparing for a behavioral interview also prepares you for other types of interview questions, and you can successfully use behavioral answers even when the question itself was not behavioral in nature.
Don't over-rehearse; you don't want to sound forced or insincere.