I can't imagine email ever being the right way to critique design, or give feedback as a client, but nevertheless it happens, and Julius Tarng, who works on the Branch app, came up with some good advice for those about to give email, and those about to receive it. I think the advice applies for any feedback that's not face to face to face including chat and in comments.

  1. Get on the the same page

  2. Talk about what you felt, not what you think the user will feel

  3. Use past tense, not present

  4. Question constructively by asking for opinions, not challenging them to convince you

  5. Try to be specific, and avoid subjective words

  6. Don’t be dramatic

  7. Give the design some time, and ask yourself if that email needs to be sent now

Don't just read this list. Read the article at Medium.