It's pretty easy. If you have created partitions for all your disk space you should shrink a volume to get hard disk space for linux installation.
- goto windows partition manager. ( click on search next to start in win 10 and type partiotion manager ) You will see all your disks and partition volumes created
- right-click on the partition which you need to shrink and click shrink volume.
- go through the process to create an empty space.
- reboot with a bootable dvd or usb of linux.
- boot into the linux distro and install as usual.
- you will be asked to install grub ( don't skip it ).
- after installation reboot
now you will see that linux and windows are listed in the bootloader ( grub menu).