For that initial traffic we literally did nothing. The page had no description, background or anything. We only uploaded the game, I pitched it to my discord (~70 active users back then) and maybe 10 of them really played it.
The most views came organically from the tags we had set (incremental, idle, clicker). After we realized that were views coming in, we then shared a gif on reddit.
If you click it, you can see that we mostly had only prototype assets. But for some reason (who knows why) the post performed really well. I think the traffic from that post snowballed us into more traffic and recommentations.
The moment we concentrated on directing that traffic to steam was when the steam page came online (1 month later). We updated all links and directed them to steam instead. We also put the big wishlist button into the game and created more reddit posts that also performed really well.