Well people could stop polluting his kingdom and killing his subjects for a start.
Okay, anyway the way the ancients Greeks used to honor the Gods was by burning food in a brazier in their name or sacrificing an animal to them, usally a goat or boar or something similar.
To honor him, of course!
To attend a banquet in his honor.
gives him the insides of cows
yes
Yes
they had religious festivals for him and built temples
the function of Poseidons temple was for Poseidons honor.
No, apollo did
Because since he ruled the seas they hoped it would help the fishing
No, there are no constellations specifically named after Poseidon, the Greek god of the sea. Poseidon is often associated with the constellation Pisces, as he is said to have created the constellation to honor the sea creatures that helped him in a battle.
Yes, ancient Greeks celebrated festivals in honor of Poseidon, the god of the sea. One of the most notable was the Panathenaic Festival in Athens, which included athletic competitions and cultural events. Additionally, the Isthmian Games, held in Corinth every two years, were dedicated to Poseidon and featured athletic contests and sacrifices in his honor. These celebrations reflected his importance in Greek mythology and maritime culture.
Poseidon himself lived under the sea, but the Greeks built several temples in his honor. Some are: in Paestum (southern Italy),Greek island of Poros, Cape Sounion near Athens, city of Corinth, and others.