Write down the purpose of your study. This should be in the form of a research question. The research question is the one question that you want to answer. For example, you might want to find out what contributes to a high school student's academic success. You would craft this into a question that can be clearly answered.
Identify your sample and sample size. Qualitative samples are generally smaller than quantitative samples. This makes it important for you to choose a sample that accurately characterizes your research question. For example, to answer the research question, you might want successful and unsuccessful high school students, since comparing both groups can help you answer the focus of your study.
Develop a research strategy. Qualitative researchers generally gather information in two ways: surveys and interviews. Surveys ask the sample to answer questions in writing, whereas interviews generally happen one-on-one. You can use both. Develop a survey that all participants answer, then create interview questions to follow up on the survey.
Execute your strategy. Remember that the purpose of drawing a qualitative sample is to find the best information possible, not to gain information from many sources. Be flexible with your strategy. If you've surveyed and interviewed an individual but still need clarification about what she's said, set up another interview. Always allow your strategy to be flexible in a way that allows you to find information that answers your research question.