How do I automatically create a blog for each new member of the community?

To enable the automatic creation of blogs for every new and approved user account, navigate to Administration and from the upper right of the administration UI, search for "Auto Create User Blog" and select it:

1. Click the Enabled checkbox.
2. Choose the Default group for new blogs in which user-specific blogs will automatically be created. Each blog is created with the username on the user account, but you can choose the group that contains the blog. We recommend that you choose a joinless or public open group so that users have access to see and post content without special permissions. It might be appropriate for your site to have a Personal Blogs group under your default group. 
3. Click Save.