Chris Chinn's Description of BW
From Burning Wiki
Characters, Beliefs, Conflict
You come up with a general idea of what the game is going to be about ("A struggle for the throne!"). Players build characters with Beliefs- ideals and goals put together, things they're willing to fight and die for.
In one kind of game, you might have all the players at cross goals, in another kind of game, they might all be working together. BW supports both very well.
Beliefs and Artha
You design your beliefs, and you either play to them, or play against them. Either way, drama happens.
Doing either, produces Artha, sort of spendable hero point bonuses to use to help dice rolls in the short run, and bumping up your stats in a big way ("Shade Shifting") in the long run.
So role playing increases your effectiveness.
Rules, Systems, Choices
The system has a simple base, which you can play with. You can choose to use the complicated subsystems for a more tactical game if you like.
Either one is fine, though both expect a level of system understanding on the parts of the players- if you are playing the basic method, you're still expected to use Helping Dice, Advantages, and augmenting with related skills ("FoRK" skills) to bump up your odds.
Both really focus on player choice and control. The more involved systems involve picking 3 actions in a "round" and revealing your choices simultaneously, both for combat or debates. Out-thinking and predicting your opposition can really swing the tide.
Having a basic idea of the system and being smart about it increases your effectiveness.
Interesting Aspects
First, you probably won't have a "perfect" character. The Lifepath system forces you to make concessions, like you might end up with "Cowardly" as a trait. Part of that is that it starts you off, a little off what you envisioned, but gives you something to struggle towards. Playing against the Traits you have not only gives you Artha, but also produces interesting play.
Second, you'll notice that I mention both role-playing and system mastery help you in effectiveness. Ideally you'll be able to do both, but if you can't, at least the game tries to help you regardless of your focus.
Aside from Artha, the primary way you advance skills and stats is through challenges- you'll want to face tough challenges to up your stats. Which means either you're up against tough things, or normal challenges while injured or otherwise debilitated.
BW works best as a long term game to really show off how it shapes and molds characters.