I live in an area with heavy Helicopter Traffic. An example of typical comms at a Heliport such as KGAO (Galliano, Louisiana) go something like this:
Filing Flight Plan with the Helicopter Owner (Company):
(Helo to Company ATC): Broussard (company ATC in charge of area), Island 1-1 (helicopter callsign).
(Company ATC to Helo): Broussard, go ahead Island 1-1.
(Helo to Company): Island 1-1 will be off of Galliano for Green Canyon 65, eta 05 after the hour, 4 souls on board, with 2.5 (hours of flight time on current fuel), Island 1-1.
(Company to Helo): (Company will repeat above)
To prepare for takeoff, the Pilot will then switch to comm 2 which they will have set to Galliano Unicom so that they can report position to nearby airspace traffic (such as other helicopters, crop dusters, fish spotting planes, etc..)
(Helo to Unicom) Galliano Traffic, Rotorcraft N660RC (tail number) off of Alpha 5 (helipad location), repositioning to the flyway (or airport taxiway if at airport), North Takeoff with a right turn out and Southwest Departure, Climb to 1 thousand 2 hundred, 0RC (abbreviated tail number).
The Pilot will reposition the Helicopter to the "flyway" (makeshift runway at most Heliports) or the airport taxiway.
(Helo to Unicom): Galliano Traffic, Rotorcraft 0RC, is on the go, Rotorcraft flyway, North Takeoff with a right turn out and Southwest Departure, Climb to 1 thousand 2 hundred, 0RC.
Helicopter will then depart the heliport to the North and climb to 300 ft., make the left hand turn to the desired southwesterly heading, and continue its climb to 1,200 ft. Helo will make two follow-up calls to the Unicom channel; one at 5 miles away from heliport, and one at 10 miles from the heliport. It will also make one follow-up call to the Company ATC; when it "beaches out" meaning when it transitions from being over land to over Gulf of Mexico Waters.
(Helo to Unicom): Galliano Traffic, Rotorcraft 0RC is 5 miles southwest of Galliano out of 1 thousand for 1,200, southwest heading, Rotorcraft 0RC.
(Helo to Company): Broussard, Island 1-1 beach out with 55 to go (minutes left to destination)
(Company to Helo): Island 1-1 is Beach Out with 55 to go (minutes left to destination), copy, Broussard)
(Helo to Unicom): Galliano Traffic, Rotorcraft 0RC is 10 miles southwest of Galliano at 1,200, southwest heading, Rotorcraft 0RC.
The pilot will then monitor the Company ATC channel on comm 2 and the customer company channel on comm 1. The Pilot will make two calls to the customer's oil platform; one call when 20 minutes out for landing (so that they may prepare the heliport for its arrival), and one call when it is 5 minutes out from landing (so that the platform personnel can give the pilot a "Green Light" to land). If for some reason the platform personnel do not respond to the 5 minute out call; or do not give the pilot a green light to land, the pilot will circle the platform until it; they answer and give the green light to land, or if radios are down, the pilot will have the company ATC make a phone call to the platform to get the green light to land and rely that back to the pilot.
As per company and FAA regulation, while offshore, the pilot is required to make a call to the company ATC every 2 hours, regardless of if they are flying around or they are shut down on a platform, to check in