It is vitally important that you pre-test your interview before administering it to your research sample. Pre-testing is the opportunity to see whether you have selected the right type of interview format, whether certain questions work better than others, and whether there are new questions or topics that should be added.
Since interview research is really about getting the perspective of a specific individual or individuals, it can be difficult at times to figure out how the actual interview will play out. Still, the first thing to do is to talk through the survey by yourself and a friend or colleague. Next, you want to try the interview out on a few others – Ideally you would like to try it out first on people who from or similar to the population that you plan to study. This would be easier if you have already been using some participatory methods that get folks involved early in the process. Still, f this is not possible, you could ask others to take on the perspective of the type of person you will be interviewing and try to react as they think they might. Take notes on and revise the interview design if things do not seem to be going smoothly.
A few additional resources on pre-testing can be found here: Cognitive-Interviewing Technique