The key to success is to treat the interview as a project, for which you must gather information, make decisions on feasibility, set objectives, identify the resources needed, draw up a plan of action, and manage the project carefully through to closure. In simple terms, you must be professionally prepared for the interview, in order to have the optimum chance of success.
No matter how expert or experienced you are, when you are applying for a promotion in your own organization, or a post in another organization, being fully prepared for the interview is critical. Your expertise, knowledge, reputation, experience, and appearance, will help you, but it is highly likely that the other candidates will have similar attributes.
Here is a list of actions that you should carry out in order to be fully prepared. Gather information about the recruiting organization (this includes your present employer if it is an internal interview): before you decide whether to attend the interview, it is essential that you gather information about the organization and analyze this. You need information on its recent and forecast performance, the condition of the business sector in which it operates, and the post that it is offering. If the organization and sector are healthy, and the post looks secure and has potential, then you can move on to the next stage. If your findings are negative then it is almost certain that the best decision would be to reject the opportunity. You need to gather information about the condition of yourself, looking at how your personal and career plans are progressing, focusing on how the prospects in your current job match with your personal and career objectives, and then how the new post could help you to achieve those objectives.
Decide to attend or not to attend the interview. You need to make an objective decision as to whether taking up this new post is the right decision for you, at this time. Armed with the information that you gathered earlier, you can assess the merits of being appointed to the new post, against staying in your current post, albeit perhaps until a more appropriate opportunity arises, and make your decision confidently. It is, of course, tempting to apply for a job which appears to offer a higher salary, more responsibility, more status, and new directions, and if this is so appealing that you are confident that you can adjust your development plans to match it, and be happy with that decision, then yes, attend the interview and perform to the best of your ability. However, be warned that the interviewers may well reject you because it will become obvious to them that the position they are offering is not a natural fit with your career to date, and worse, they may well ask you how this new opportunity fits with your future personal development plans, and be disappointed with your unconvincing response.
Gather details of the job itself. You need as much information as you can gather about the nature of the job, the role, responsibilities, reporting relationships, location of the workplace, working conditions, and conditions of employment such as working hours, holidays, and corporate policies and procedures that apply to the position. Some of this information will be given to you in the information pack sent to you by the interviewing organization, or department, but often, sadly, the quality of information sent out is poor. Most professional organizations will have HR departments that will answer your questions on these issues, or pass you on to the appropriate line manager.
Research the interview format: you need to do some basic but essential research on the practicalities of the interview. Again, some of this information will be sent to you. You should be clear about: how to get to the organization and the specific interview location (don’t rely on asking for this information when you arrive, as this adds to the stress of the occasion); who is on the interview panel (their titles will give you important clues as to their relationships to the post); what format the interview will take (there is nothing worse than arriving expecting a traditional face-to-face interview and finding that it is a day-long series of tests, group activities, and interviews).
Timing of arrival. Make sure that you arrive in good time, allowing time to tidy your physical appearance after your journey and sufficient time to become calm before the actual interview.
Your appearance. Do not make the mistake of thinking that it is only your history, qualifications, skills, and knowledge that will win you the job. Most other candidates will have similar attributes, so you need to make an impression, to look professional, smart, and appropriate for the post. In many cases, there will have been a previous holder of the post that the interviewers may be using, albeit subconsciously, as a benchmark.