do you have any suggestions on how to advertise?
If you are going to be an affiliate, the most common/effective approach would be to sign up for and create blog, or similar site, write articles related to the topic and post the affiliate link. Making videos and posting your link on the description is also a good way to promote your link.
In most cases, affiliates don't advertise in the sense that a service provider would. Affiliates provide content to information hungry visitors, gain their trust, and, in related articles, they will explain why a certain product/service is worth buying.
It is a sad fact of life that most affiliates have no idea why they're recommending a product, other than the large potential commission.