I like to follow the Recap Monday threads and check what people are playing. Often enough there's someone playing a cool game I never heard of before.
I haven't done this in a while but I still believe watching dice tower's Week in Review series is a fantastic way to find out new games. They give very short summaries of the game they played that week and rate it. If something catches your eye you can dig deeper and find out more about the game. The only drawback is that sometimes the games they play take a long time to be released in Europe, which is a real bummer. They reviewed Turing Machine 11 months before the game was released in Portugal.
BGG's Hotness page is also a cool way to find games. Go to the hotness page and ignore all recent or unreleased games. To make it simple, I ignore all games of the current year. If a game survives 1-2 years in the Hotness page it's certainly worth checking out. Current games that fit this criteria are Ark Nova, Heat: Pedal to the Metal, Dune: Imperium, Brass: Birmingham, Spirit Island, Lost Ruins of Arnak, Terraforming Mars... Certainly games worth checking out.
Finally, I like to buy games with mechanics that I don't have in my collection. Recently bought Ready Set Bet because I didn't have any "pure" betting game. Ordered Dorfromantik because I don't have any game with tile laying.
If you're on the fence between a couple of games you can always ask the people you're going to play with for opinions. More often than not it helps to at least narrow it down. If they can't help, we can! Ask the community!