Men’s skin care is often an overlooked factor in headshot photography. Using a good moisturizer will help your skin look great in photos. Also, be sure to drink plenty of water in the days leading up to your shoot as it helps keep your skin hydrated.
With regards to facial hair, make sure you give it a fresh trim as you’d typically wear it on a daily basis. When shaving, try and use a sharp blade as it’ll reduce the amount of skin rashes and nicks that come from using dull blades.
Also, make sure any nose and ear hairs are taken care of!