Well formed hints will ensure a higher response rate and data of a higher quality. Respondents won't have to think about what you meant by asking certain questions and how to fill them in, they will simply follow your instructions.
Adding a descriptive help text
Go to the survey builder and choose the question you want to edit.
Double click the chosen question or select Edit in the bubble.
The second box, right under the Question title, is the extra description. It can be edited as you please, as well as deleted if you don’t want it there at all. When you're done editing this field, simply click save.
Tip: The extra description can be an important part of the questions in a survey, especially when using more complicated instructions or question types etc. You can inform the respondent how exactly you want the question to be filled-out. E.g. “Choose more than 2 options”, “Explanatory notes: 1 - excellent, 2 - good , 3 - sufficient, 4 - bad, 5 - very bad”.