Plan first, gather second. Decide who you'll ask, how many, where, and how you'll record their answers. Sloppy gathering ruins good questions.
Checklist before you start
- Sample size — at least 30 for any pattern to emerge
- Random selection — don't only ask your friends
- Same wording every time — read the question, don't paraphrase
- Record immediately — memory is unreliable
A small carefully-gathered sample beats a huge messy one. Quality first, quantity second.