In preparing the chicken for truffling, it is necessary to separate the skin from the meat. This is done quite easily once the thin membrane connecting the two is broken. Pull the neck skin back over the breast and you will find the membrane. Holding the skin up, puncture the membrane with your fingernail and spread it apart with your fingers. Once under the skin, you will find that you can easily slide your hand along the surface of the meat. As you reach down toward the leg and second joint, you will find your way impeded by another membrane. Break this one and your hand will slide over the leg.