The Precision Bass® has perhaps the least complex wiring setup of any electronic instrument, simply follow the diagram below.
For typical Jazz Bass® wiring, the two volume controls blend the signals of the two pickups independently. Unlike most other guitar wiring, the output wires from the pickups connect to the middle lugs of the volume pots, letting you turn the volume of one pickup down without affecting the other.
Reduce unwanted electrical noise by using shielded coaxial cable for your longer wiring runs (for example, the connection between the controls and the output jack). Coaxial cable contains a center (hot) conductor which is shielded by an outer braid used for the ground wire.
For short connections between components, use standard non-shielded wire. Typically, white wire is used for hot and black for ground.