Happy Loki Day, everybody.
Of course, nobody knows what rites were used to honor Loki in the ancient days, or what days were sacred to him, but many Lokians I have known use today. For obvious reasons.
As the Lokian who taught me about it described it, today is a day where Loki should be given a sumbel of his own, where each participant recites as many of Loki’s heiti as possible, and recites all of his deeds that they know. Today should be a serious day: no joking, no laughs. Formal clothing is encouraged, and time should be put aside for contemplation of Loki’s mysteries.
May it bring you much insight.