In a typical tar-and-feathers attack, the object of a crowd's anger would be stripped to the waist (if not below). Hot tar was either poured or painted onto the person while he (rarely she) was immobilized.
Then the victim either had feathers thrown on him or was rolled around on a pile of feathers so that they stuck to the sticky tar.
Often the victim was then paraded around town on a cart or a rail. The feathers would stick to the tar for days, making the person's sentence clear to the public.
The aim was to hurt and humiliate a person enough to leave town and cause no more mischief.
The Bostonians Paying the Excise-Man , 1774 British propaganda print referring to the tarring and feathering of Boston Commissioner of Customs John Malcolm four weeks after the Boston Tea Party. The men also poured hot tea down Malcolm's throat as can be seen.