1) The extruder should come with a thermistor (Figure 15) which measures temperature, a heating element (Figure 16), and an extruder head (Figure 17). The thermistor and heating element both go into holes on the extruder head as shown in Figure 17.
2) Use electrical tape to bundle all the wires together and move them away from the printer mechanisms. Screw the extruder head into the main body of the extruder using the hole labeled in Figure 18.
3) Press rubber tube for filament into the extruder body.