What kind of product do you have? My main feedback is to find a handful (5-10) possible places to promote your product where your audience really lives. This could be writing a guest post on a targeted blog, announcing your product on a Facebook/reddit/Slack group where your theoretical users live, etc. You want to get a handful of passionate users as quickly as possible. This will not only create some great evangelists for your brand, but will also let you hone in on what your ideal users really care about in your product. From there, you can fix any problems and dive deeper into marketing to those audiences.