To prevent seasickness on the boat tours in Gansbaai, prior preparation is essential. It is beneficial to have a light meal before boarding and avoid excessive alcohol consumption. Drink plenty of water to maintain fluid balance. Consider wearing acupressure bracelets. Over-the-counter medications may also be useful; it is recommended to take them a few hours before traveling. Always focus on the horizon, get fresh air on deck, and move with the motion of the ship. If you are prone to seasickness, choose a cabin near the middle where movement is least.