Many receive the gift through the laying on of hands. Some experience laughter by watching videos of Rodney Howard-Browne. In other words, people coming to a Revival group see and experience people laughing. They receive teaching on the gift and are prayed over so that the gift manifests itself. Many see other people experiencing this gift in the large prayer group but experience it for themselves in a smaller setting, or by the laying on of hands.
Holy laughter is an abiding gift.
Once a person has experienced this touch of God, they tend to experience it again and again, usually during a prayer gathering but also privately. The laughter can happen any time or any place, although the person can exercise some control over the gift. The greatest and deepest experiences occurs in the Revival group where praise and prophecies prepare the person for this manifestation. As the group continues to yield to the Revival manifestations, more of the members come into the gift of laughter. No reason exists why this gift cannot be for everyone just as the charismatic experiences of Baptism of the Spirit and praying in tongues were for all.