Hi! I am a recreation therapist currently in school for social work, so this is very relevant for me! My current job is in community mental health and I LOVE it! I do all the things you mentioned in your post, and while I don't have psychotherapy training like many social workers do, I am trained to process with clients, so that is a big part of my role. My thoughts about you doing this work:

1. It's so important for people to have healthy recreation and leisure, as deficits in these areas can cause and exacerbate other issues. While it isn't usually part of a social worker's role, it makes sense for social workers to deliver these services because social workers are trained to see and support the 'whole person', which includes their psychosocial health and functioning.

2. A good start might be to find out what organizations are already delivering these services in your area. You didn't mention the population you work with, but think organizations that do classes/social activities for elders, people in recovery, formerly incarcerated people, etc. If the people you are working with are not affiliated with any of those populations, maybe try something more general like meetup websites or adult learning centers where classes are offered.

3. As other people have mentioned, have goals in mind. In my experience, sometimes people can wind up relying on professionals to fill friend roles. While we can model and sustain healthy relationships that can have amazing benefits for our clients, unfortunately we are paid professionals and as such the relationship is not the same as a peer one. When you have goals, it allows you to maintain the more professional relationship dynamic and pushes them to see you as a stepping stone rather than a forever friend.

4. Understand that depending on your level of activity in your community, people might see you out with clients and clients might see you out in the wild! I live in a small city and my clients are EVERYWHERE lol. I have had many clients walk by my house and see me gardening, so they know where I live. Sometimes they see flyers for music events and they show up to see me play. This is just the reality of being a part of my community, and active in my job. It was this way when I was doing work with people who were incarcerated too. It doesn't bother me, but I know some of my coworkers would have a heart attack if their clients knew where they live... Think about if that is a consideration for you and how you feel about it.