train travel to santa Margherita

chris, The best rail station to use will probably depend on what time your flight arrives. Regardless of whether you use Piazza-Principe or Nervi, you won't have long to wait for a train. The airport is only 7 kM from the city centre, so in the same situation I'd just take a Taxi to Genova Piazza-Principe and buy a ticket at a Kiosk for the next departure to Santa Margherita. Note that your destination station will be shown as Santa Margherita Ligure-Portofino. As the train you'll be using will likely be a Regionale, DON'T FORGET to validate your tickets prior to boarding the train, or you may get hit with a hefty fine which will be collected on the spot! When you arrive at Santa Margherita, you'll probably have to take a Taxi again to reach your hotel. The station is located on a hill above the town. If you're energetic and travelling light, you could also walk down the long stairway to street level and then to your hotel. It's mostly level once you get down the stairs. Happy travels!

Taxi or Volabus. The bus stops at both main stations (Piazza Principe and Brignole).
Trains will stop in both stations (Piazza Principe first then Brignole) so you can use either one. Driving from the airport, Piazza Principe comes first. If you take the taxi, use that one and you will save a couple of euro in taxi fare. If you take the Volabus, I don't know if the bus ticket is the same price for both.

Chris, if you are looking up the your destination train station on Trenitalia, the name will be Santa Margherita Ligure-Portofino. The trip takes about 40 minutes from Genova.