You should check out @basv 's Makerbox it comes with so many useful marketing tips and strategies which I'm currently using.
https://www.producthunt.com/prod...
I would recommend reading the 1-page Marketing Plan (Get new customers,make more money, and stand out from the crowd) by Allan Dib. Had many useful tips and techniques that I would have overlooked.
I think it depends on the product and target audience. if you think the audience is Gen Z you can use influence marketing, if more old school try newspapers and pamphlets. You can also research similar products and take inspiration from what work for them