The typical thing is to put up a profile on one of the big three swinger sites: Swinglifestyle (SLS), SDC or Kasidie. I think all of them allow you to put up a profile for free, but it's very limited. Use it to find out if there's an acceptable number of profiles in your area. (Search for paid members, free members won't get you anything.) Then, when you've decided on one, pay for your profile. It's not that expensive - about $15 a month, less if you go for an extended plan.
Now comes the work. Think hard about what you want on your profile, think of it as trying to make a first impression. You should have at least a couple of photographs on the site, they don't have to be revealing or nudes, feel free to blur your faces, or cut your heads off altogether. Then wait for invitations, and reach out to whomever makes you warm.
You can find a complete listing of swingers clubs on SLS at https://www.swinglifestyle.com/swingers/clubs/ Are they weird, can you watch, etc? Take a look at the posts in swingers clubs forum on this site. (Simple answer, every club is different, you can always do what you want, unless you try to pressure somebody else. I've never been to one which is just one big orgy, although I bet there's some out there.)
Have fun!