I've copied the following guidelines from Harwood Institute's "Authentic Engagement" framework. Not only are they helpful during community discussions but ideal in all areas of person-to-person engagement, including interacting with youth during library programming and working with colleagues in committees.
Have a "kitchen table" conversation of no more than fifteen people so everyone can participate and no one dominates.
There are no "right answers" since we all draw on unique experiences, views, and beliefs.
Keep an open mind, and listen carefully to try and understand the views of others, especially those who are different than yours.
Keep the discussion on track by sticking to the questions and not rambling.
It is okay to disagree, but don't be disagreeable. Respond to others as you want to be responded to.