The Klingon wedding was a highly ritualized ceremony, resembling an opera. Klingon warriors beating their drums received the couple as the officiant (usually the Lady of the Great House of the groom) recited the traditional story of the Klingon creation, in which the second Klingon heart was created to be joined with the first and they both rose up against their gods. The Tawi'Yan presented the couple with bat'leths as they did mock battle with each other in representation of the struggle of the two Klingon hearts against one another.
After the couple recited their vows, swearing to unite against all their opponents, the guests attacked them with ceremonial weapons, the ma'Stakas.
In preparation for the wedding, brides joining their betrothed's house had to be approved by the mistress of that house. The bride needed to display her ability to perform several traditional Klingon rituals, e.g., the Bre'Nan and the display of Var'Hama candles. Brides were also required to recite the history of all the females of the house she was joining. Grooms prepared with their closest male friends, including one designated as the Tawi'Yan, the Klingon equivalent of a best man. They went to a cave, or a simulation of a cave if necessary, for the physical and spiritual journey of kal'Hyah. (DS9: "You Are Cordially Invited")
Klingons could also be wed in a shorter, more informal ceremony in which the two participants repeated an oath and then kissed. This ceremony could be performed by the Klingon equivalent of a justice of the peace, or the vow could be taken privately, legally constituting marriage by mutual consent. (DS9: "The House of Quark"; TNG: "Reunion")
Writer Ronald D. Moore stated that he "carefully crafted the marriage ceremony to emphasize the importance of women in Klingon society: the ceremony is conducted by a woman, and the story of the first two Klingon hearts describes them as each bringing different components to a union, with neither one having dominion over the other." (AOL chat, 1998)