A day-of-coordinator will handle tasks such as managing vendors, overseeing the timeline, and troubleshooting issues. They ensure the day runs smoothly but will not replace a wedding planner or handle pre-wedding preparations. They will not dictate creative choices or be responsible for choosing decorations, but they will execute the plans made by the couple. Their role is to provide support, assistance, and organization on the day of the event, ensuring everything goes according to plan.