Libraries Need Friends: Starting a Friends Group or Revitalizing the One You Have (PDF, 100 kb) by Sally Gardner Reed, former Executive Director, United for Libraries, is a free toolkit geared mostly toward public library Friends groups, but with good tips on membership and outreach for Friends groups of any type.
https://www.ala.org/united/sites/ala.org.united/files/content/friends/orgtools/libraries-need-friends.pdf
ALA: Organizational Tools for Friends Groups
https://www.ala.org/united/friends/orgtools
Sign up for the Friends Discussion list to learn about events and ask questions to other Friends across the state.
https://mblc.state.ma.us/sympa/info/friends
Attend a monthly Friends Coffee hour connect with other Friends across the state.