Facial hair can really compliment a guy with long hair. Choosing a particular style of facial hair requires a lot of experimentation and sometimes the proper grooming (sideburns, mustache, goatee). When it comes down to it, don't be afraid to try something new. You'll never know whether you like it or not.
Some other long haired guys found that this can be a great way to eliminate confusion, like being mistaken as a girl. Overall though, it's just a great way to pull together a certain look.
The most important thing to remember is to have fun with it. Certain facial hair work better with certain occasions. You'll go through many different phases, and you'll be bound to change it up frequently until you find something you really like. Although, if you do have trouble growing out facial hair, remember, a clean shave is always in style and will look good. Have thin facial hair? Try Just for Men, it can really thicken the appearance of your facial hair.
Again, if you're not sure whether a type of facial hairstyle will work for you, ask your friends or your hairstylist. If you are one with weak facial hair, it's probably best to keep a clean shave until you can fully develop those hair follicles.
To see lot of pictures and hairstyles, check out this page: Pictures