You can find a list of active campaigns on this page: Ongoing Campaigns. On that directory page, you will find a link to individual pages for various campaigns including Religious Reproductive Rights, After School Satan, Sober Faction, and more. Each of these pages has a contact form that will let you submit your information if you would like to find out how to join the team and volunteer for the campaign.
After you find a campaign that captures your interest and you submit your inquiry using the form on their page, please be patient. Remember that TST is an all-volunteer organization: some groups only meet once a week, and some groups meet less often than that. You may receive a reply within 24 hours, but you shouldn’t be surprised if you do not. If you make a couple of attempts to contact a campaign and receive no reply, it is possible that the campaign is simply not accepting new applicants at this time. You can always try again later in the year. In the mean time, you may want to reach out to a different campaign or find a Congregation near you.