dual booting

Hi.
Ok first off I have opensuse 13.1 install on my 150g hard drive.
What I want to do is install windows 7 on my computer and dual boot.
How do I go about installing windows 7 without deleting my current partition with opensuse.
I know I'm going to have to resize my hard drive partitions and everything and im willing to.
Can someone explain it to me step by step please.
Thank you.