Method 1
The Old Method of Sharing a Post via Email Still Works. To do that:
Make a post on your Google+.
Share the post with the Gmail ID of the person you want to invite to Google+.
The person receives a post via email with a join link.
Method 2 – Mobile > Google+Login Page > Signup for Google+
This method was used by some of my friends to signup for a new Google+ Account. [Credits - Saketh Reddy]
Open your Mobile Browser.
Go to plus.google.com
Click Sign In.
If you are not already joined it, You will be given a Sign Up form to join Google+.
Use that form to add yourself to Google+.
The Old Method of Sharing a Post via Email Still Works. To do that:
Make a post on your Google+.
Share the post with the Gmail ID of the person you want to invite to Google+.
The person receives a post via email with a join link.
Method 2 – Mobile > Google+Login Page > Signup for Google+
This method was used by some of my friends to signup for a new Google+ Account. [Credits - Saketh Reddy]
Open your Mobile Browser.
Go to plus.google.com
Click Sign In.
If you are not already joined it, You will be given a Sign Up form to join Google+.
Use that form to add yourself to Google+.