Wear a hat. Bring sunscreen and use it, especially if wearing shorts. Make sure any kids do, too. Portaging Expect to get your feet wet. Rocks at or near the surface of the water can rock and roll.
Wet rocks are slippery.
A layer of algae makes them more so. The more heroic the effort to keep one's feet dry at a portage, the more likely they are to get wet, and the more heightened the probability of sprained ankles and similar unpleasantness. Your footware should be appropriate for carrying heavy loads over broken terrain. Save the beachware for camp. This is not a beach.