Step 1: Materials
AA or AAA 2-battery holder
Step 2: The doorbell
Step 3: Complete the circuit
Now solder the negative wire from the buzzer to the negative wire from the battery pack. then solder the positive wire from the buzzer to a wire coming from the doorbell and the positive wire from the battery pack to the other wire from the doorbell. I used heatshrink tubing to cover up the wires. Now just put in the batteries and test it out to make sure it works.
NOTE: I wired the wires backwards. You should hook up the red wires to the switch and not the black like i did.