
Rent a bike and ride it the full 26km round trip to Punta Uva.
The local bus leaves 4-5 times a day direct from Caribe Station in San José. Last bus leaves at 4pm and all buses are direct with one pit stop outside of Limon. The ride is approx 4 hours. Make sure you get on the bus to Puerto Viejo de Talamanca, not de Sarapiquí which is a different part of the country ( see www.thebusschedule.com).
If you want to save a few colones, you can take local bus from Caribe station to Limón and transfer to Puerto Viejo bus. This is what many locals do.
There are also tourist buses that will pick you up at your hotel and drop you off where you want. The most popular one is Interbus. There is also EasyRide and Grayline.
Driving here is also popular, but roads can be bad as at certain times of the year, the pot holes can get obnoxious. However, you really don't need a car when you are here. Most people rent bicycles and scooters. The roads may not be all paved, but they are flat as they all follow beach line.
The bus system is excellent. Most lodges have bicycles for rent too.