Optimize and populate your page with content first: It's never a good idea to start promoting something before it's truly "ready," whether it's a new blog, a new campaign, or a new social presence. Spend some time optimizing your Google+ page and building it up with content and posts before you start promoting your presence. This way, when new visitors land on your page, they'll have a rich, positive experience that engages them. You need to convince them that your page offers such remarkable value that they'd be missing out by not following you.