Some great advice from Sarah Hamaker at Crosswalk.com
https://www.crosswalk.com/family/parenting/how-to-handle-discipline-in-public.html
Starts with describing.....
Three Ways to Handle Discipline in Public
1. Help your child calm down first.
2. Keep it private.
3. Keep shame out of it.
Goes on to explain prevention.....
1. Layout expectations before you leave the house.
2. Roleplay each situation.
3. Practice, practice, practice.
4. Prepare ahead of time.
5. Reward good behavior—sometimes.
Check it out!
https://www.crosswalk.com/family/parenting/how-to-handle-discipline-in-public.html