From what I've personally experienced, good tagging, naming and labeling does help quite a bit. I've noticed that our games sometimes show up when someone clicks through another game of the same tag, or they pop up when someone filters through tags. There are also some who search through the bar at the top - that one filters in games with matching titles.
Another way is to join game jams. Don't submit games you didn't make for them, though - join them properly. If you can make a good game that's relevant to the theme, there'll likely be a spillover audience looking for more from the same developer who'll visit your profile and play your older games.
Imo the best form of marketing for game devs is our reputation as developers - work of a quality we can be proud of plus content that suits our brand and style. Even our experiments say things about us sometimes!