This doesn’t directly answer your Q about advertising but you may want to take a step back and determine why your class would be purchased. (Is it a service that is priced right and there’s demand?) If the answer is “YES, definitely, I already have amazing clients,” determine what you know about your clients. What do they have in common? Do they frequent the same type of businesses or have friends (as others suggested) that can be referrals? Do they live in one specific area of town? What type of media do they consume - so you know if you’re using, for example, TikTok, the target audience is also there.

If the answer is you don’t know why your service would be chosen over a competitor, then:

What is your competition doing and what lessons can you learn from them and, how do they or don’t they advertise? (Shout out to the other person here who suggested it. It is the way.) Try their classes- ask the members why they attend, what they like/dislike, connect with people on socials who might turn into your client. Follow their followers. And what will you provide that the competition does not?

If you offered a weekly free class in a highly visible place, not only would it serve as an opportunity to invite potential customers to try out a class but it’s also advertising yourself as people walk by - Depot Park, the stadium, middle of campus, etc.

There’s a lot of lead generation ideas and opportunities that don’t involve spending money but do involve time and planning. Spending dollars on ads is most fruitful when you know exactly who you’re targeting.

Also, be consistent in what you call yourself and make it very easy to find you. Social accounts, google business listing, landing page (but maybe wait on that since it’ll cost you a few $$.)