Crepe wool is excellent for creating Mo's and Beards. There are a range of different styles you can create and i have posted some here for your convienience, you can also order it pre made into beards and mo's..It is cheap and handy,  you apply it with Spirit gum (Also known as Mastix ) and take it off with Spirit gum remover ( mastix remover ). You will find some online stores i have advertised both here in Australia and in the states just to help you out if you dont know anywhere to buy it from..
~ Excellent Crepe wool info ~
a simple page for facial hair designs
http://jan.ucc.nau.edu/~jec3/FacialHair/FacialHair.htm#Mustaches
What suits your face?

For a realistic look it may be an advantage to take into consideration your facial shape and features before making your final choice about how much or how little hair you should grow: Just for you, because you rock! Here are some tips:
Long, thin face. You don�t really need to add to the length of your face, so a long beard and goatees  will just add length to your chin, unless that is what you want. Your best options are sideburns to fill out your jaw line. Alternatively, a wide moustache can work, as it draws attention away from the lower half of your face. If you do want a full beard, keep it trimmed very tightly around your chin and leave the sides fuller to fill out the jaw area.
Round, full face. If Your aim is to lengthen the face, a goatee may work. It gives the effect of narrowing the face into a point at the chin and takes from the fullness of the jaws. Avoid any hair on the jaw line or a narrow moustache � these only add to the roundness of your face, once again, unless that it what you want.
Small chin. Your best option to bring out a small chin is to grow a goatee. A full beard can also work well, drawing out the chin. Never go for a moustache alone, though, as it will further overshadow your chin.
Square jaw. A full, rounded beard works well here, as it will soften the square look of your face, unless that it what you want.. If you plan to add sideburns, keep them narrow.
Bald head. A minimal beard, trimmed very tightly, can work well. A goatee can also be successful for some, but avoid any fuller styles. Sideburns need to extend from the hairline, so you may want to avoid these.
Covering scars. Certainly facial hair can be an excellent way to cover scars. However, it's still important to combine the hair cover you need with a style that suits you. Don't haphazardly produce a full beard just to cover the scarred area. You may be able to cover it with a well-groomed goatee or creative beard style. Grow the full beard first, mark the area you need covered and style accordingly.
How to Apply a False Moustache and Beard

For Moustaches:

Prepare the area by patting or spraying Barrier Spray on the skin. Paint a layer of Spirit Gum on to the skin and let it dry completely. Both will act as a shield against perspiration which can loosen the moustache. Paint another layer of Spirit Gum on the skin and press the moustache firmly against the skin, positioning it carefully. Press the edges down and Smile to check that you haven't glued over your smile lines by mistake!

For Beards:

Unless you have a sweaty chin you will not need the first layer of spirit gum so follow the above routine, leaving out Step #2, being careful to center the beard on your chin.

Note: If you are using a fake beard or mousatche be sure to use the Barrier Spray, even though this step can be omitted if they are only to be worn for a short time. Always remove the Spirit Gum with Spirit Gum Remover.
Quick tip:
If you are looking for the more realistic look, it is good to mix more than one colour of crepe wool together when desinging a mo or beard.
Practice makes perfect...theres no time like the present, start designing or looking at different types of side burns, mo's, beards etc etc so you have a guidline to work off if you feel a bit daunted by how to create facial hair.

There might be one that suits you more than another. Above all dont be affraid to jump right on in and start dabbling with facial hair, just make sure you have the necessary things to do it safely, Its a good idea to test the adhesives on your skin before using it.
Australian site's to purchase crepe wool
Houston, Tx costume store with crepe wool
Victoria
http://www.frankelcostume.com/index.html
Adelaide: The Stage Shop, 3 Leigh st
Adelaide city
82319554
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