Configure the Excel template for import.
Save the file as an .xlsx file.
Consult the collaborators list.
Click on the 'Import' button (↑).
Indicate whether or not you want to automatically confirm the email addresses and/or notify the users by email.
Select the file you want to import.
Click on 'Start import'.
Link each field from your file to the correct field in Beeple.
Click on 'Modify' import data'.
You see an example of what will be imported.
Click on 'Import'.
You receive the result of the import. If there were failed rows, you can download an Excel file which contains the errors. Update this file (delete the 'error column') and import it again if necessary.