File Sharing With Windows 10

I have a file sharing question.

I am using OS X 10.11.1, my coworker is using Windows 10.
I have a folder on my iMac that I want to share.
My coworker needs to read and write to these folder.

I have both computers set up to this this. My coworker is able to read, write and edit files as needed.
I used this method to allow access: http://www.howtogeek.com/howto/24950/how-to-share-a-folder-in-os-x-with-windows/


Here is the problem: When she saves a new file or saves an edited file, I no longer have read/write access to that file. How do I setup the Windows side to save the file so I have read/write privileges on the Mac side?

More Info: The folder in question is located within my home folder.
From System Preferences > Sharing I signed her a user name and password.