I realized after the fact this might be misinterpreted as "Didn't market, LOL" which is definitely not the case! Spent a ton of time trying to build awareness & pent-up demand before launch, just not in the most overt, traditional ways. Here's what I did:
I put up a Steam Coming soon page at the same time I announced the game, so any initial interest could immediately be 'locked in' via the wishlist system. I believe those wishlists are very important to accrue - seems to feed Steam traffic & boost day 1 sales.
My marketing materials weren't finalized at that time - launch was still 6-8 months away - but I had a short trailer that I invested a lot of time in and seemed to get the point across well. Did get some initial Steam traffic when Coming Soon created, so treat as mini-launch.
At the same time, I started an open beta to gather feedback on the game. I organized this on a Discord server (highly recommended). Players who were interested notified their favorite youtubers, who then started asking for keys.
At that point I've got a small community growing on Discord, fed by some YouTube traffic. beta key requests starting coming in too fast, so I set up an
@itchio page (highly recommended) with limited copies available for sale, so people could buy into the beta.
This way, I've got a set of testers that are highly motivated. Others can simply add to their wishlist. The growing wishlist numbers seemed to feed the game into Steam's traffic algorithm, showing up on other game 'more like this' pages = positive feedback loop
Also, selling on Itchio seemed to generate its own traffic, as it's easier to break into the top charts there. So I think got additional visibility from that
Meanwhile, more YouTubers are asking for keys, so I keep sending them out. I'm also tracking a set of targeted YouTube channels that are into the genre - had good luck with those 10K to 100K subs channels, seemed to have fanbase dedicated to genre
(whereas channels with Million+ sub channels get lots of views, but viewers tend to want to watch the performer, not caring as much about the game itself, and probably less likely to do a full series)
About 1-2 weeks before launch I contacted YouTube channels that hadn't covered it, and gave heads up to previous channels that big update coming out & may want to cover again.
By this point I have a better trailer & concise pitch, and there's a bit of buzz, so the channels I hadn't had bites from yet had probably at least seen the game around. These factors meant that almost all channels I contacted made a video.
So by launch day I've already had videos from dozens of channels, some of them are a series, all of which keep feeding the wishlist cycle - So by launch day have tens of thousands of wishlists, and tons of YT video views.
Launch day comes, the email goes out to wishlisters, and even though only a fraction buy on day 1, it's enough people that it gets a foodhold on the chart. About 50% of day 1 purchases were from those that had wishlisted it. The other half probably came from resulting chart vis.
Other factors I think come into play - I picked a title that very clearly expresses what the game is. You can understand the game in a gif. It's a 'popular niche' genre that is very popular on PC, and particularly on Steam, and yet relatively underserved.
The things I didn't do: cold-email sites asking for reviews, use a publisher, pay for ads, show at expos. I honestly do not know if they would have helped MORE, but at least they were not a
necessary step here
Usual caveat - every game is different, presumably there's some secret sauce about the game itself here, and in 1-2 years everything may change again? But I'd say keys are: pre-launch community building, and making sure Coming Soon page was up to collect wishlists.
Ooh and forgot one key thing- add tags to your game page on Steam! They seem to be very important for letting Steam algorithm know if your game is similar to others. Check out other games in your genre if you need suggestions for relevant tags