Provide postage-paid envelopes for returns. With that in mind, you may want to start your analysis with a survey to achieve breadth and follow up with focus groups. It can make people defensive and feel that they need to provide an answer. Take people back to an experience or have them look ahead and define a set of objectives. Ask uncued questions first, cued questions second.
Cues are the hints or prompts that help participants recall specific features or details.
Standardize questions if a number of focus groups will be held. Write questions in complete sentences. Focus your questions, using a sequence that moves from general to specific. Ask sensitive questions last.