If your dog bites someone its natural that you as the owner would feel panicked because you don't know what to do or what might happen. Here are a few pointers on what are some good steps to take if something like this were ever to happen.
-Obviously stay calm, not only will it help your situation but your reaction and mood will definitely affect your dog.
-Crate your dog or put him/her in a confined area.
-Help the person that got bit wash the wound with soapy warm water.
-Don't get defensive or start blaming each other.
-Get medical help (varies with severity) and exchange contact info (and insurance if needed) with the victim.
-If there were witnesses get their information.
-Contact your vet to get your dogs medical history and contact local authorities.
*** Check your municipal code to see what the cities laws are regarding dog bites. This way you are well prepared for what might happen.
*** Its important to take responsibility for the incident and offer to pay medical expenses. This is also a good way to hopefully avoid a lawsuit.