From Juan Santamaría airport take the panamerican highway going North towards Puntarenas. Stay on the highway for 10-15 minutes, until you see an exit for a town called Atenas. Take this exit and continue to follow the signs for Jacó and Quepos, as you go through the towns of Atenas, San Mateo, Orotina. Once you hit the Costanera, keep driving and look for signs to Jacó.