Not a full time gravity falls watcher , but how do I watch season 2?

Don't get me wrong , I love the show . I've been watching it since middle school , and I'm in highschool now. I always thought it was just a random plot epsiode each time , with no real canon story but I heard that season 2 is so intense with storyline that I want to watch it but idk how. I've seen re runs and random episodes on cable when ever I can , but I don't think I've ever follwed up on the real story line. The only thing I can get from season one I'm assuming is that Stan has a vending machine lab with 2 of the books dipper has and he's not what he seems. How does season two handle this? Is there any filler or non Canon episodes on that season? What can I skip?