The easiest way to get a feel for a new activity is to try it. However, it can't always be Wednesday night, so a few videos of the way we play this sport might help to get the idea across.
For events and inter-realm meetups, combatants develop some form of 'garb' with a medieval or fantasy theme, sometimes with an elaborate character story. This adds atmosphere to the sport without really affecting the game play in any way. The ability to win within the game will only come from practice and effort. At weekly practices within An Tir Dearg you are expected to wear loose comfortable clothing you can train in (jeans are discouraged).
This first video is where a group starts, the nightime park or backyard sparring session. The sport is a combination of individual fighting skills, honed in sparring sessions like this, and small and large group tactics learned at larger practices and regional events.