Geneva is the closest major airport, roughly an hour by car in normal conditions. Drivers usually reach Samoëns via the A40 motorway and the valley road through Cluses and Taninges.
By public transport, take a train to Cluses and continue by regional bus toward Samoëns and Sixt-Fer-à-Cheval. Services vary by season, so check the current timetable before relying on a late connection.