Basically you adjust the blue knob/thingy with a small Phillips screwdriver to adjust the wattage you want to
vape at (it tops at 15,) put the kick on the kick ring of the mech
mod, or just way up top where the positive pin of the mech would touch the pin/plate on the kick, put your battery in, with the positive touching the bulge below the kick, and there you go (based on the Kick2 by evolv, as that the only one I have.)
Hope it was clear enough and helps, if not I can try to get some pics up later when I arrive home.
Oh, and you should use a battery size smaller than the tube(s)/tube combination allows to. E.g. If your mech is sized for an 18650, use an 18500 instead to allow for the kick.