Final answer:
Barricades should be placed in a visible location at the start to ensure safety and clear guidance for traffic redirection.
Step-by-step explanation:
When using barricades for directing traffic, they should be placed in a visible location at the beginning. This visibility ensures that drivers have ample time to understand the traffic changes and to follow the new route safely. Barricades are crucial for maintaining safety and order on the roads, especially in areas with construction, accidents, or special events. They provide clear guidance to drivers, helping to prevent confusion and potential accidents.