Cut pin 2 (Drain pin) as we will use the top drain instead.
The offload resistor (5k) should be installed between the gate (Pin 1) and source (Pin 3). Remember to isolate so you don't get sparks flying :-)
The Gate resistor should be installed on the gate. This protects the mosfet so that it doesn’t overload the gate. Again remember to isolate! Depending on where on your gun you are planning to hide the mosfet you can solder on this resistor in different so it's utilizes space the most.
Your mosfet is ready. Now it's time to solder it to your gun
In The Gun
The Gate (after the resistor) should connect to the trigger. The Drain should connect to the motor negative side (Black). And source to battery negative (Battery black). The other side of the trigger and motor positive (Red) should connect directly to battery positive (Red).
That's it you’re done :-)
When you install, solder everything or it will break! Isolate all connections so it doesn’t short out. The better the battery the less stress on the mosfet (durability) so get a good LiPo 20C minimum!
This mosfet is a basic one, if you want more you can look for "Active breaking" and "Burst mode" mosfets. These mosfets has additional features. But for most guns the above is sufficient.