In guided practice, walk up, praise one thing that is already working, give a single prompt for the next attempt, and walk away. The prompt is phrased as what to do, and the error itself is never named, because naming it reinforces a picture of the student doing it wrong.

What the instructor says

• Praise. “Nice pickup”, “super acceleration” — name what is already good.
• Prompt. One correction: “stop at two o’clock”, not “you’re going back too far” — tell them what to do right instead of what they did wrong.
• Leave. Then leave and let them do it; walk back later with “man, you got that.”
• Correct the positive. Naming the error reinforces a picture of them doing it wrong, and it is a very hard habit to break, even for him. This tactic prevents negative language, and it works better as well as feeling better for the student.

Putting it to work

1. Watch one cast before you speak.
2. Praise one real thing.
3. Give one prompt — a place, a cue, a line — never a diagnosis.
4. Leave for a few casts, then return with praise.

Source

From the FFI CI walkthrough series by Dayle Mazzarella (Chapter 3 — FFI Casting Instructor Certification Tasks, Fly Fishing Coach International), lesson 15 part 2, 00:07:10 and 00:07:42. See the video library for the series and the CI exam section for the teaching tasks; terms follow the FFI Fly Casting Definitions.