Here is some excellent info about using the public bus here which is quite easy to use once you try it once or twice.
At each bus stop, there is a sign with a map of bus routes on the front and a schedule on the back. The maps are written in Japanese, but if you know the route number and destination, you can find the final destination on the map by following the route numbers on the roads.
Route numbers one through 17 are categorized as the City (Naha) Line and numbers 20 and greater are the Suburban Line.
You may need to take one bus route to a terminal in order to transfer to a different route. There are seven suburban terminals and one Naha city terminal.
Passengers must remember to enter the bus through the front and exit through the rear for the Naha city bus
The City Line destination sign has a route number, destination and main bus stop whereas the Suburban Line destination sign has a route number and main bus stop, followed by the name of the terminal.
Getting on a Suburban Line bus you will enter and exit through the front door. These buses are destined for Naha Bus Terminal.
Upon entering the bus, the you need to take a ticket from the ticket machine and find a seat. Before each stop, the driver will announce the name of the bus stop over the intercom. It is best to learn the name of the stop before the final destination is reached. This saves a lot of confusion and walking to get back to the intended bus stop.
Once the stop has been announced, you must press the button near the window to tell to the driver to stop.
When the bus stops, take the ticket and match the number to the board display beside the bus driver. This is the amount of fare to pay before getting off the bus. The fare can only be paid in Yen.
Before departing the bus, you will put the ticket with exact change into a box on top of the fare collection box. Passengers without the correct amount of Yen can put in a ?1,000 to make change in the collection box.
The link below lists all the bus routes and numbers on Okinawa.
The absolute best way to get around Okinawa is to have a car. There is the bus which goes to the major places, but to get off the beaten path a car is needed; in some cases, a 4WD vehicle is even better to get to some of the secluded beaches and dive spots.
Back to the driving, if you have ever driven in any drive-on-the left country, you will be comfortable driving here. That said, there are a couple of dangers I must warn you of.
First, the max speed limit here is 80kph. This is pretty slow by western standards and this is on the expressway. Do not speed! Fines are hefty and there are cameras everywhere. There are also unmarked vehicles out to catch speeders and reckless drivers. Beware the purple Skyline GTR. Yes I said purple. The Skyline can easily be considered the most powerful car available in Japan and the Okinawan police have a purple one as an unmarked chase vehicle. Your poor under powered rental van or econobox could never get away from it. I will try and get a photo of it and post it the next time iI see it.
Second, when it rains here, due to the coral composition of the roads and coral dust mixed with suface oil, the roads get EXTREMELY slippery. It is like driving on talcum powder mixed with oil. I would rather have an icy street anytime over this stuff.
Okinawan drivers are extremely polite; to a fault. They will come to a stop even when there is no sign for them if you are already there at the intersection. They will let you turn right in front of them if it appears you have been waiting to turn for a while; even though they have the right-of way. Rarely is a horn blown in anger or stress. They drive just as carefree as everything.
Finally, make sure you park in a legal parking space. Parking fines are excessive and you will get towed. You will be charged a towing fee, in addition to the ticket and you will be charged a storage fee for your car while you search for it. Pay the 300yen to park in a garage or pay lot.