I've been running classes out of my garage since the beginning of the year.
We did free classes by appointment only for the first 3 mo. Then it got a bit hectic trying to do that, deal with no-shows and keep my full time job so we started charging. That cut down the playing field from 20 folks to 8. Much more manageable now.
I'd like to stay at my place the rest of the spring & summer and build up more clients and focus on the ones I have now.
Make them into walking billboards. You can obviously do this by training them properly etc, but also getting t shirts and whatnot help spread the word too.
Try looking into doing some community events or training at a local park wearing your gear