Steel and iron when burned let you see blue lines connecting yourself to every ferromagnetic object, push with steel and it flies directly away from you, pull with iron and it flies directly toward you, along that line... if the object strikes something along the way you can use it as an anchor, so a steel misting can push a coin into a person, or the ground, and be shoved directly away from it. Same an iron misting could pull a coin toward them and have it get intercepted by something and pull themselves toward it. Large metal objects or metal coated objects - like a statue or a flagpole or a sword stuck in a stone can let you pull yourself toward it or push away, iron and steel respectively. This lets mistborn fly though in a somewhat pogostick bouncy ball kinda trajectory, and 'Coinshots' people who can burn steel. Iron misitng are called Lurchers because the can make someone clad in or holding metal lurch I assume.

The actual game effect is kinda hard to interpret, Lurchers are usually defensive in nature and walk around with sturdy shields (tower shields I think) so they can drag metal-tipped projectiles toward them and I think also to steady themselves with them while yanking on things. Coinshots are essentially machine guns. Your guess is as good as mine about role effect but a Steel Misting probably would fit either some sort of attack role whereas iron mistings would probably be defensive or perhaps some sort of RB effect of scrambling actions but that would seem a stretch.