Is your smoker normal (two wires with a white plug) or proportional (2 wires to a white plug, 2 sets of 2 wires with bare ends)

If its a normal non-prop smoker, simply connect it with a switch (so you can shut it off), to the battery.

If proportional, the plug end needs snipping off and wiring to the battery (again, with a switch) and the other 2 sets of 2 go to each motor (for "sense" of how much smoke to produce)