How to Post to Specific People on Google+
When you're ready to post content on Google+, you need to figure out whom to post to. You can post to specific people and groups to ensure that your content is shared exactly the way you want. For example, you can post to circles (groups of contacts), individuals, or e-mail addresses.
Posting to circles on Google+
When you choose to post to a circle of friends or contacts, your post is visible only to that circle. Keep in mind that even though you're posting to a specific circle, only the people you've circled will see the post.
To be sure that everyone you’re targeting in the circle sees your post, mouse over the circle name after you enter it in the Add More People box, and a new pop-up dialog box will appear (as shown in the first figure below).
Just check the box next to Notify About This Post, and now everyone in that circle will receive a notification about your post. Be sure you’re not spamming them when you do this, though! If people believe you're spamming, they may very well block your posts.
Posting to individuals on Google+
In addition to circles, you can post to individual members of Google+. To post to an individual, type the person's name in the Add More People box rather than the name of a circle. To send to multiple individuals, add more individual names (see the figure below).
To enter a name, always start by entering a plus (+) sign. This is a good habit — with this method, you can also tag people in posts.
Posting to e-mail addresses on Google+
What if the individual isn’t on Google+? Or what if you can’t find them? Just type an e-mail address in place of the individual's name or a circle name in the Add More People box and an e-mail will be sent to that e-mail address with the content of your post.
Knowing who will see your Google+ posts and how they'll see the posts
You can check any time to see how others will view your posts and your profile information. To see how others can see your profile and posts, follow these steps:
Go to your profile page.
To get there you can either click on your name in the upper left or click on the profile icon at the top.
Click View Profile As.
You’ll see this link in the upper right in the grayish bar with links to your About page, Buzz, Photos, and so on. After you click it a text box appears.
Enter the name of a specific individual or a circle.
A drop-down menu . . . drops down.
Select the same individual or circle as you did in Step 3.
Click through each part of your profile to see how that individual or circle is seeing your profile and click on Posts to see which of your posts they’re seeing.
Click Done at the top to go back to your profile.