Beards are to men what makeup is to women. Make sure you are applying it well. For those that were not blessed with lumberjack genetics, here are some ways, not to mention self-care you should be doing anyways, to make your beard appear more full.
Comb your beard
Stimulation to the hair follicle is the best way to promote hair growth. Similarly, the way the hair on your head needs some taming, the hair in your beard needs the same. Commonly, combing your beard along with proper maintenance will help maintain the proper shape.
Wash and condition
Although a little bit different in density and texture, treat the hair in your beard the same as the hair on your head. There are products specially formulated for your beard for a reason. Healthy skin equals healthy hair.
Ask your barber for a taper
A properly trained barber knows how to perform magic. Areas that appear less dense can be faded into areas that are more dense giving you a sharper and more full appearance.