The present disclosure provides a wound dressing assembly comprising (i) a blood-clotting mold device having an enclosure defined between walls of a main body and a removable closure over an opening and is configured for introduction of blood thereinto, and (ii) a coagulation initiator in an amount sufficient to coagulate blood introduced into the enclosure to form a blood clot, wherein the formed blood clot is transferable onto a wound. Also provided by the present disclosure is a method for preparing a wound dressing by introducing a volume of blood into the enclosure of the blood-clotting mold device, maintaining the blood within the enclosure for a time sufficient to permit clotting of the blood to thereby obtain a blood clot； removing said closure to open the enclosure； and extracting the blood clot from the enclosure. The blood clot thus formed may be used in a method for dressing a wound by fixation of the clot onto the wound, which method also forms part of the present disclosure.
