To give yourself insulin using a needle and syringe:
Pinch up some skin, and quickly insert the needle. Keep the skin pinched to avoid having the insulin go into the muscle. (Depending upon your body type, you may not need to pinch up a fold of skin.)
Push the plunger down all of the way.
Let go of the skin, and remove the needle. If you can see blood or clear fluid (insulin) where the shot went in, press on the area for 5 to 8 seconds, but do not rub.