When enjoying a walk in the Wadden Sea in front of the coast, you must take some simple precautions as the rising waters can be dangerous. If you are far from the beach and the tide surprises you, your life will be in danger.
Always remain within sight of the land, and do not walk out too far. Take care of fog and mist. Enter the area only after high and prior to low tide, and return shortly after low tide, i.e. as soon as the water starts to return and the high tide sets in. Keep a watch with accurate time, and memorize the times of low and high tide. The water does not rise in all places at the same speed. Some areas are lower, and Priele creek-like arms or canals of water can well flood very early, cutting you off from land.
You should ask for advice and rules on-location; there are several lifeguard stations and most tourist information places will be able to provide you with basic information as well. Ask for a tidal calendar German: Tidenkalender.