Install windows 7 after windows 10 already installed

Has anyone installed windows 7 after windows 10,
(duel boot)
will be using different HD to do so
if so whats the best way to go about it.
would like to avoid reinstalling 10.
ty for some info
Answer #1
It should be fine..Once you installed Windows 7 it will create a dual boot..
Answer #2
The guy here with the screenshots seems to think it is easy enough..
http://www.tenforums.com/installation-setup/26369-windows-10-windows-7-dual-boot.html
If there are any problems with booting you could try a program like EasyBCD.