Open the Mail app on your iPhone, iPad, or Mac
Start a new email
Add the file or attachment you want to send
If the attachment is too large, Mail may prompt you to use Mail Drop
Tap or click Use Mail Drop
Send the email
Wait for the upload to finish
The recipient receives a download link instead of the file attached directly
Make sure Mail Drop is enabled in your iCloud settings
Use Mail Drop only with supported file sizes and attachment types
Check that you are signed in to iCloud
Ensure the recipient can access the download link before it expires