Hi, you can see a sneak preview of how approval flow interactions would look in this video here (https://youtu.be/2d4TwyvBh8M?t=6)
As for best practices - checkout this talk I gave at OWASP- https://youtu.be/A5adHlkmdC0.
Message us on our slack community (https://bit.ly/permit-slack) for early access to the feature.