Multibooting special question [Windows 10 and Mac OS X]

[Mediotaku23]

Hi, I´m new in the forum so sorry if some things i´m gonna ask here should be obviously know by me.
I have a brand new portable hdd of 1 Tb and a Pc with Windows 10 installed in a SSD, with another hdd for extra storage, I only wanna know if it would be possible to create in the new hdd two partitions, one of around 100-150 Gbs with Mac Os X installed and the rest of the disk in another partition that would be used for extra storage for my Windows 10. The idea is that I can do multibooting every time a turn on the pc.
I know that this may be tricky or impossible but I wanna know if this is possible before getting sure my pc is fully compatible with Sierra, thank you all.

 

[Going Bald]

Hi, I´m new in the forum so sorry if some things i´m gonna ask here should be obviously know by me.
I have a brand new portable hdd of 1 Tb and a Pc with Windows 10 installed in a SSD, with another hdd for extra storage, I only wanna know if it would be possible to create in the new hdd two partitions, one of around 100-150 Gbs with Mac Os X installed and the rest of the disk in another partition that would be used for extra storage for my Windows 10. The idea is that I can do multibooting every time a turn on the pc.
I know that this may be tricky or impossible but I wanna know if this is possible before getting sure my pc is fully compatible with Sierra, thank you all.

Are you booting UEFI mode?
Back up files on second drive to external drive. Disconnect Win10 drive. Boot Mac OS installer and use Mac Disk Utility to format the drive 2 partitions sized as you like, both of them formatted GUID partition tables for Mac OS. Install Mac OS, run MultiBeast post install and get it booting from the drive and audio/networking/etc. working. Shutdown, reconnect Win10 drive and boot Win10 by selecting the drive using the Function hot key during POST to allow you to select a boot device.
In Win10, open the disk management tool. Click on the second partition of the Mac OS/Storage drive and select Actions->Format and format the partition NTFS. Shutdown. See the Dual boot UEFI on separate drives Guide pinned at the top of this forum for setting up the dual boot.

 

[Mediotaku23]

Are you booting UEFI mode?
Back up files on second drive to external drive. Disconnect Win10 drive. Boot Mac OS installer and use Mac Disk Utility to format the drive 2 partitions sized as you like, both of them formatted GUID partition tables for Mac OS. Install Mac OS, run MultiBeast post install and get it booting from the drive and audio/networking/etc. working. Shutdown, reconnect Win10 drive and boot Win10 by selecting the drive using the Function hot key during POST to allow you to select a boot device.
In Win10, open the disk management tool. Click on the second partition of the Mac OS/Storage drive and select Actions->Format and format the partition NTFS. Shutdown. See the Dual boot UEFI on separate drives Guide pinned at the top of this forum for setting up the dual boot.

Umm ok I think I understand most of the process. I have some questions. What do you mean with "Back up files on second drive to external drive" ? Do i need to back up the files on my storage windows10 drive to my new external drive? or with "external drive" do you mean a fourth drive for back up the windows 10 files?Do I need to do it?. And why do i need to disconnect the windows 10 ssd before plugging and booting the Mac installer usb for the new 1 Tb drive?.
I really appreciate your help, thank you and the forum community.

 

[Going Bald]

Umm ok I think I understand most of the process. I have some questions. What do you mean with "Back up files on second drive to external drive" ? Do i need to back up the files on my storage windows10 drive to my new external drive? or with "external drive" do you mean a fourth drive for back up the windows 10 files?Do I need to do it?. And why do i need to disconnect the windows 10 ssd before plugging and booting the Mac installer usb for the new 1 Tb drive?.
I really appreciate your help, thank you and the forum community.

I mean backup any files on the Win10 storage drive so you do not lose them.
Disconnecting all drives except the target drive when installing any OS is advised. It prevents mistakes and, in the case of Windows, makes sure all of the boot/recovery files are on the same drive.