Instructions on building a potentiometer

Gather the materials needed to make a potentiometer: a resistive element, a wiper, a shaft, and a housing.
Connect the resistive element to the housing. Make sure the element is securely connected so it does not move or break.
Place the wiper on the shaft, and attach it to the resistive element. Make sure the wiper can move freely along the resistive element.
Place the shaft into the housing, and secure it in place.
Connect the two ends of the resistive element to the housing. This will allow current to flow through the element.
Test the potentiometer to make sure it is functioning correctly. Adjust the wiper to different positions along the resistive element and measure the voltage output.
If the potentiometer is functioning correctly, it is ready to be used.