Copacabana Wave Hostel'e yol tarifleri

From the airport/bus station:

Take the bus called Leblon from outside the terminal. The name of the bus company is REAL. It will cost you some R$9 and will take approximately one hour.

Ask the driver to drop you at Rua Miguel Lemos at the beach avenue. Walk two blocks through Rua Miguel Lemos, cross two streets and take the left at the third one - Travessa Cristiano Lacorte (before the a bus stop - there's a sign at the corner saying Wave Hostel).

You can also take a taxi (R$75) from outside the terminal but give preference to the ones registered by the airport, with "kiosks" inside the arrival lounge. They also take payment in advance with your credit card. This avoids surprises on the cost and saves you some cash right in the beginning of the trip.