Wash and dry your beard
Comb the beard downward
Find your Adam’s apple
Place two fingers above the Adam’s apple
Imagine a curved line from behind one ear to the other, passing just above that point
Mark the neckline lightly if needed
Trim everything below the neckline
Use a trimmer with a guard or a razor for a cleaner edge
Shave slowly and carefully under the line
Keep the neckline natural and slightly curved
Check both sides for symmetry
Clean up stray hairs after trimming
Moisturize the skin after finishing