Testing for voltage with a multimeter can be quite handy. First, set your multimeter to the voltage setting, often symbolized by a "V" with a straight line for DC or a wavy line for AC. Then, place the probes on the circuit: the black probe on the ground or negative side, and the red one on the positive side or where you're measuring. Be mindful of safety and starting on a higher setting to prevent damage. Have you had much experience using a multimeter before, or is this your first time trying?