Classicist scholar Jon Mikalson identified the six steps of collective ritual in ancient Hellas: the process can be used for any routine communal religious activity. (This structure is also the chief way to celebrate festivals as a groups but we’ll get more into holy days later.)

0. Selection of priests through election or random lots as suggested by Plato. According to the Oxford Handbook of the Ancient Greek religion, priests “had no special religious training or knowledge to bring to their office. What expertise they had was acquired on the job.”

1. Procession to the place of worship lead by the priest, processions can be solemn affairs or joyous parades like mardi gras revelry. Ancient plays describe how procession participants sang hymns but it would be better to have everyone chant a god’s eitphets instead of choreographing a musical or simply remain silent. Music can also be played during processions: cymbals and tamborines correspond to Dionysus. Participants could carry objects associated with the gods: pinecones for Dionysus, five seashells on a string when worshipping Aphrodite, guns and swords for Ares etc.

2. A hymn is sung after reaching the place of worship; the are many ways to perform this step – the priest could lead the entire group in reciting the invocation. In Roman polytheism only priests recited hymns and prayers during group worship or the hymn could be recited by a select chorus while everyone else remains silent.

3. The priest recites a prayer loudly while everyone else repeats his words. (Prayers could also only be recited by the priest or a chorus.)

4. The priest makes a large offering to the god that’s thrown onto fire. In the past animals would have been sacrificed at this stage but modern priests can simply burn large offerings of meat, incense, libations etc.

5. Events and celebration dedicated to the god; dancing, athletic competitions and music etc. It would be good (but not required) for the festivities to correspond to the god, people worshiping Artemis could have an archery competition at this stage while Poseidon’s worshipers could have a pool party or swimming race.

6. Feasting.

Offerings to ouranic gods should be burnt a few feet above ground while offerings to chthonic gods should be burned in a hole: worship to the olympians is directed to the sky, worship to the underworld deities is pointed down. A BBQ fire bowl on a stack of logs would make a perfect altar to any ouranic enties since you don’t need a replica of an ancient marble altar: just a fire above ground. You can also build a large bonfire or campfire to take the place of an altar; any fire used to worship the olympians should be built on a mound or point above ground level while any fire to the chthonic beings should be in a pit. A pack of pagans have no need for a temple, sanctuary or altar as long as the priest burns the offerings a few feet above ground level.

A modern religious event could consist of a parade to a campground where participants gather around the priest to recite an Homeric hymn to Aphrodite. Then the priest recites a prayer to Aphrodite while the group repeats each word before having the cleric give a large cut of lamb (heavy with fat) to the fire. Then the group would have a party with music about Aphrodite on speakers and sit down to a lamb dinner.