Major events like Comiket attract enormous crowds, sometimes exceeding 500,000 attendees over multiple days. Arrive early as lines can be extremely long, especially on opening day. Bring cash as many independent vendors don't accept cards, wear comfortable shoes for extensive walking, and consider bringing water and snacks. Check event-specific rules regarding photography, cosplay policies, and prohibited items. During summer events, the venue can be very hot, so dress appropriately and stay hydrated.