How do you level up?

[MetalRenard]

I love systems which reward you for every action completed. Skyrim does this well - swing a sword enough and your sword skill goes up. Run and jump all the time and your stamina goes up. I think turn-based RPGs could do this too - every attack gives you XP based on how tough the enemy is and how much damage you do, even if you don't kill them. Open many doors and maybe you won't hit your shield on the frame as you go through, next time...