Start with the closet edge of the wound to you face and sew away from yourself.
You will notice that the immediate edge of the wound would have become numb and will be able to be pierced with little to no discomfort.
Make sure you keep as close to the edge as possible without it hemoraging and releasing the stitch.
We will start to the left of the wound with a initial holding stitch.
Insert the needle downwards through to the sub-dermal layer of the skin. At this point you will need to level off the needle and venture through the wound and to the adjacent wall of the wound.
Once across the other side of the wound return the needle to the skins surface through the sub-dermal layers of skin.
We need the needle to go deep enough as to not release the skin through a tear.
Once we have reached the right hand side of the wound we need to make a diagonal path across the wound again to the next point. The simple diagram will illustrate.