Knocked out tooth: Wash tooth in water holding it by the crown (not roots) then put tooth back in socket. If you cannot get the tooth repositioned, either place tooth inside the cheek, or in milk, water or a damp towel. It is important that the tooth does not dry out.
For the best possible chance of saving the tooth you must go to a dentist within 30 minutes.
Broken tooth: Clean debris from the injured area with warm water. If caused by a blow, place a cold compress on the face next to the injured tooth to minimize swelling. Call a dental surgery for an appointment as soon as possible.
Bitten Tongue or Lip: Apply direct pressure to the bleeding area with a clean cloth. If swollen, apply cold compresses. If bleeding does not stop readily or if the bite is severe, go to a dentist or hospital.