Committees, commissions, and special panels hold hearings. You can express your opinion and show that it has community support.
Find out the place, date, and time of the hearing. Ask the sponsor or your representative for this information.
Be on time. Some public hearings take testimony in the order of those signing in.
Fill the room with supporters. Have them bring posters, if they are allowed. But make sure your supporters do not antagonize the committee.