I was fortunate enough to witness a Smash scene blossom in SoCal. Project M back in demo 2.0. Before then, people definitely played and had side tournaments to Brawl nights at the usual venues. But when enough of us were gathering on Facebook and other chatrooms, we quickly surpassed Brawl as the main event. Turning 20 entrant days to 40 entrants, to 70-100 for bi-weeklies. The attention PM was getting exploded throughout 2012, and I was just a high school senior making hour long drives to Super Arcade to play with friends. One point I want to make is that waiting for a scene to develop around you is not an option. Smash 4 is not going to get any more popular over time. Yes, it still gets updates, but people that play other fighting games already know how they feel about Smash 4. And they're not interested in joining the game unless they're convinced things have changed, or it's more interesting than they first thought.
So, my advice is get in touch with as many dedicated players as you can. Start a regional Facebook group, investigate your school for other players, look up whatever major tourney venues in your state have at least side tournaments for Smash. You might be surprised. If there's a Melee scene in your area, you may already be good in asking them to host Smash 4 on the side. I don't have any experience starting a tournament. But you can always use your own home as a venue for when things are still small. Definitely host smashfests for players to fight people other than siblings and usual friends. There's nothing more hype than seeing that one guy who's doing crazy things with Samus or Pac-Man that you've never seen. I've heard of people writing all kinds of guides on this site for tournaments and building a smash scene.
