linny First boot Solus live USB and partition the hard drive. Use GParted to make 1 partition for windows (NTFS), 1 for Solus (ext4), and make a 3rd partition with a size of 256-512mb for Solus ESP (fat 32).
Don't install Solus yet, boot windows from usb to install it.
After that install Solus. I recommend using separate ESPs (Efi System Partition) for Solus and windows. You need to open GParted and set boot and ESP flags for the 3rd partition you created. This will be the ESP partition of your Solus install.
You can now use the Solus installer. Select manual partitioning (or whatever it's called), select the partition you made for Solus when the step comes, in a later step you will need to select the ESP partition you'd created before for Solus as the location of the bootloader.
The reason I recommend using separate ESP partitions, is that windows sometimes screws up the bootloader of other operating systems, so it's best to keep it separate from other OSs.
If you want to be extra safe, like me, use separate drives for 2 systems, as this pretty much guarantees windows won't screw up your Linux install.
