Boot camp assistant works great, but it will install Windows in legacy boot mode and will prevent access to integrated graphics. If you want to install with native UEFI access and permit integrated graphics, do this instead.
Mostly follow this guide: https://fgimian.github.io/blog/2016/03/12/installing-windows-10-on-a-mac-without-bootcamp/
EXCEPT: Do not use unetbootin to create your Windows USB image. Instead, use a Windows machine and create your bootable USB with Microsoft's USB installer tool. This will grab necessary installation files from the web, so don't bother with downloading an ISO ahead of time. After using the tool to prepare your USB drive, copy your 'Windows Support Software' to the USB drive.
So basically:
- Open Disk Utility
- Shrink your macOS volume
- Create a FAT partition for Windows
- Open Boot Camp Assistant
- Download Windows Support Files
- On a Windows box
- Use Microsoft's USB installer to prepare a Win 10 install USB
- Copy over the Boot Camp Windows Support Files to the USB drive
- Reboot your Mac, holding option key for boot menu
- Select EFI Boot
- Windows installer launches. Delete the FAT partition you created, and add a new partition to install.
- Proceed with Windows installation.
- When Windows finishes install, install the Boot Camp Windows Support Files to install necessary drivers/software.
I had enabled secure boot initially. I'm not sure if this is required or not, but it might be.
ISSUES:
- Runs pretty hot, not sure if some power mgmt config is missing
- On-board audio output via Intel HDA not available
NOTE: Unlike when installed through Boot Camp assistant, the Intel HD 4000 device is available in Device Manager. However, I can't seem to get integrated graphics to actually be used. I've tried installing rEFInd and setting spoof_osx_version to be sure, but this does not appear to help. Using 0xbb's gpu-switch does appear to correctly set Integrated mode, but rebooting into Windows gives a black screen shortly after the Windows boot animation.