It's as rough as it gets. You really have to know who your customer is. Not as a thesis, but as a proven. If you can find your exact customer base, you will get customers over and over again. There is one subreddit where I can post any time of the day and will have 50-100 new testers by the morning (and if it does extremely well then 10x those numbers). It's way more niche and specific for most products than people think, spamming X won't help build brand identity unless you are following and talking to your literal customer. Then persistance, persistance and more persistance. P.S I am an absolute amateur at this as well but just my experience.