Backup Strategy For Both Mac and Boot Camp on Single Drive


I have a MacBook Pro (High Sierra) and a Boot Camp partition running Windows 10. I have a 4TB external drive which I would like to use to backup both the Mac and the Windows data. Can anyone suggest a good approach please?

Should I split the drive into 2 partitions, point Time Machine to one and use the other for Winclone? If so, how should I format each partition?