From the Job Manager, select the individual candidates you would like to share.
From the Actions drop-down menu, select Share.
You will get this pop-up menu where you can add email recipients and comments. The comments are not required.
Your contact will receive an email like this one:
By following the link, the hiring manager will be able to review candidates, leave comments, and let you know that s/he has completed the review.
Note: anyone with the link can view the shared candidates, whether or no he or she is a user on your account.