Because its runway is too short for international flights, the best way to reach La Gomera is the 40-minute ferry ride from Tenerife several times a day into San Sebastián's busy port. Most of the travelers are day-trippers. Turboprop planes island-hop into the airport near Playa Santiago from other islands in the archipelago, but only one flight arrives a day. Roads are rugged, to say the least, with many hair-pin curves but amazing vistas.
Cars can be rented by the day from a number of agencies, including Hertz and Europcar. The most offices can be found in San Sebastián and Valle Gran Rey and at the airport near Playa Santiago.
Mountain bikers can explore challenging ravines and forests in a climate that's never too hot or too cold. Trails, sometimes old donkey paths, can accommodate beginners to advanced with local cycle-guides conducting day tours at different levels of difficulty. Motor bikes and scooters can also be rented.
The aqua public buses are easily recognized, but the network is minimal with only a few trips a day. If you have to be a specific place at a specific time, choose some other way to get there. And always check the day before to see that the schedule hasn't changed.
Taxis are a good bet and good value at about 50 cents/km on the meter (check it when you get in). They have a price list for longer hauls around the island. You'll find taxies at port jetties and every town has its own service.