Staying calm while planning a last-minute wedding involves prioritizing tasks and maintaining perspective. Begin by creating a streamlined checklist that focuses on essential elements like venue, guest list, and attire. Allow yourself to delegate responsibilities to trusted friends or family members, which can alleviate stress and foster collaboration. Remember to breathe and take short breaks to gather your thoughts; even a few minutes of quiet can help you regain focus. Embrace flexibility, as unexpected changes may arise, and keep in mind that the goal is to celebrate love rather than achieving perfection. Celebrate small victories