Experts recommend backing up QuickBooks files frequently, especially before making major changes. Using a flash drive for this is simple and safe. Insert the drive, go to File → Create Backup, and save your company file. If you run payroll or enter daily transactions, consider backing up every day. Weekly backups are a minimum requirement for most businesses. Keeping multiple dated copies on your flash drive ensures that even if recent data is corrupted, you can restore an older, stable version.