Doug King: Just like rules for operating on the road, there are rules on the water. These are called the International Regulations For Preventing Collision At Sea, and they're adopted across Australia, and designed for orderly navigation on the water.
There are some basic rules for all mariners. You must keep a proper lookout at all times, and in all directions. This is to assess the risk of collision. The second is to maintain a proper speed, or a safe speed. A safe speed is one that will allow you to avoid a collision, and you need to take into account how fast you're going, what other traffic there is around, visibility, sea conditions. And the third general rule is that power boats give way to sailing vessels, and power driven vessels include personal watercraft.
When you're operating in narrow channels, keep to the right-hand side. If you're meeting another vessel head-on, both vessels alter course to starboard or to the right. If you're crossing or meeting a vessel from the side, you give way to the vessel on the starboard side. In other words, give way to the right. And finally, if you are overtaken, you can pass either side, but keep a safe distance. And the vessel that's being overtaken should maintain course and speed. If you have to give way or avoid another vessel, take early action and make it clear, so the other boat knows you have seen them and you're going to give way.
At nighttime, you must display lights. Power-driven vessels have to display a port and starboard light. That's red and green, plus a white masthead light, and a stern light. Sailing vessels show the same lights, but don't have to show a masthead light. Lights also have to be displayed in restricted visibility, such as fog, heavy rain, bushfire smoke, those types of situations.
There are some other special rules. They're common sense, mainly. Stay clear of large ships. Stay clear of tugs and berthing operations if you're around a port. Also, make sure that you stay clear of vessels displaying the diver's flag. This is a blue and white flag that has to be displayed when diving operations are underway. The rules of the road are as important as the buoy system. They're for orderly navigation and a proper knowledge of them is required. More information is available from good boating publications and your state boating guide.