4A feedback guidelines

Giving feedback
1. Aim to assist. Feedback must be given with positive intent. You should describe how your feedback can help the person (not you!).
2. Actionable. Feedback must focus on what the recipient can do differently. It shoudn't be just the expression of your emotions.
Receiving feedback
1. Appreciate. Naturally we don't like feedback and try to argue or make excuses. You must force yourself to appreciate the feedback.
2. Accept or decline. You must always listen to all the feedback. But you decide if you are following it or not.

You should also give feedback everywhere and always. Just when it helps the most, doesn't matter how many people will hear it.