You must also register with the Stones River National Cemetery. 

https://www.eventbrite.com/e/stones-river-national-cemetery-memorial-day-flag-placement-tickets-310738686777

Scouting and other youth organizations from middle Tennessee will place American flags on more than 7,000 graves in Stones River National Cemetery. In order to ensure adequate parking and space for physical distancing, groups of volunteers will place flags starting on the hour from 9 AM through 4 PM. Volunteers will park in the overflow parking area near the visitor center and check-in near the walk-in entrance to Stones River National Cemetery. No volunteer parking in the cemetery.

Volunteers should plan on arriving no more than ten (10) minutes prior to their appointment time and must leave the national cemetery prior to the next group's start time. Volunteers will receive flags and section assignments at check-in.

Volunteer groups may pre-register for a commemorative patch through the Middle Tennessee Council - Boy Scouts of America.