There are plenty of times when pulling your hair up away from your face or neck will be more comfortable. When it's hot or you must bend over for any length of time, having your hair up is far more convenient and perhaps even more attractive. If there is no hair implement available, a quick bun can be made with a pencil.
Comb your hair with your fingers to get rid of any tangles. Your hair should be fairly smooth before making the bun so that no pieces of hair are sticking out from it.
Use both hands to twist your hair in the back. Depending on the length of your hair, this may be done in the middle of the back of the head, on the top or the bottom. Shorter hair generally will only make a bun in the middle.
Keep twisting your hair until all of it is twisted into a tight rope of hair. Make it tight enough to hold the hair together, but not so tight that a pencil won't be able to pass through it.
Hold the top of the line of hair in one hand and the bottom of the line of hair in the other. Move the bottom part of the line around the base of it and keep winding it until all of it is in a compact spiral against your head. Hold the spiral in place with the hand that held the end of the rope of hair.
Take a pencil in your other hand and stick it into one side of the spiral, through the entire mass of hair and out the other side. It sometimes takes a little bit of jostling with your hair to get the pencil to go all the way through the spiral. If the pencil won't go through, your hair was wound too tightly. If your hair falls out of the bun, it was wound too loosely.