Order of Exposures (Article ID 83)
Abstract: Although there is no rule about placing exposures in the order of the hand as shown on the card, it is courteous to do so. Jokers should also be placed among the pung, kong or quint they belong to.
Question from a player: When mah jongg is declared, is it necessary for the player to expose their hand in the same order as shown on the card?
Answer from the NMJL: “A player is not required to place exposures in the order in which they are shown on the card; however, when Mah Jongg is declared, tiles should be re-arranged to show the correct order.”
Source: Mah Jongg Made Easy 2020 page 14
Other answers from the NMJL:
“Be courteous. Mah jongg should be exposed in the same order as shown on the card. Jokers, if part of the hand, should be put in their correct place.”
Sources for other answers: National Mah Jongg League Bulletin Q&A (1996 page 5, 1997 page 5) https://www.nationalmahjonggleague.org