Walk around the recording space and click your fingers at ear-height. Depending on what type of room you are in, you'll detect a range of acoustic responses to the click. If you are in an acoustically treated vocal booth, the entire space will be dead and the click won't echo at all, in which case, you can set microphone in any part of the room. If you are recording in a bedroom or other non-studio space, find the deadest spot in the room before setting up the stand. The deadest is spot is the one where your click echoes the least.
Set up the microphone stand and put a piece of electrical tape on the ground, 6 inches away from the stand, between the stand and the nearest wall. This is to show the singer where to stand. It's essential he doesn't deviate from this position. Although the majority of the sound is projected from the mouth, baritone and bass register voices resonate in the chest as well. By positioning the microphone in front of the singer, you will capture some the chest resonance too.
Adjust the telescopic microphone stand so the microphone collar is approximately 1 inch below the singer's mouth. When recording, it's preferable for the singer to project their voice over, rather than into, the microphone capsule.
Slide a condenser mic into the stand collar. A condenser is preferable for recording a baritone vocal as it is sufficiently sensitive to capture the projected voice and any associated ambiance, but it is not so delicate that loud singing will cause it to overload, as would a ribbon microphone.
Adjust the arm of the pop shield so the shield itself sits approximately 1 inch in front of the microphone, between the mic and the singer. The pop shield intercepts strong airflow from the singer's mouth, reducing the "pop" effect caused by over-projection of the voice.
Connect the female end of an XLR cable to the microphone. Connect the male end to the "XLR Input" jack on the compressor. A compressor enables you to temper the dynamic range of the input signal. Since the baritone voice can be projected powerfully or delivered softly, there is a wide range of possible dynamics. Using a compressor smooths out those dynamics and cuts out any volume "spikes" caused by going from soft to quiet.
Connect a 1/4-inch jack cable to the "Output" jack on compressor. Connect the other end to the 1/4-inch input jack on the mixing desk.
Connect a pair of headphones to the "Mix Out" jack on the mixing desk channel to which the compressor is connected. This enables your singer to hear the backing track without the backing track feeding into the microphone.