“Go to matches”
Volleyball coaches spend a lot of time watching volleyball. They watch the games their team plays. They watch the video of those games, often more than once. They watch multiple matches of their upcoming opponents, often more than once. They watch practice of their team, and often the video of those practices too. If there is still some time left in the week, they watch some matches livestreamed on the internet, probably from one of the top leagues in the world. But how often do they go to watch matches, live in the stadium (gym)?
Watching scouting videos from the perfect position behind the court gives a particular perspective of the game. It is often considered the best perspective but even then it is still only one perspective and a single fixed camera, no matter how high definition only gives part of the story. Watching in person gives you a match better ability to judge the quality of sets, the movement of the players, and where and when players feel pressure to name just a few things. It gives you a better opportunity see signals and other communication between players to get an insight into tactics that are being used and their effectiveness. You nearly always learn something new from watching matches live.
Plus volleyball is fun, and you will meet cool people.