When migrating data to Office 365 https://exclaimer.com/email-signature-handbook/mastering-office-365-data-migration-for-seamless-transitions/ , it's crucial to plan meticulously, especially for large volumes of emails and files. Start with a full audit of existing systems, ensuring data compatibility. Prioritize phased migration to minimize downtime, and train users for a smooth transition. Compliance and security are key, so regulatory requirements must be met throughout. Following best practices outlined in Exclaimer’s Office 365 migration guide ensures a seamless and secure migration.