Add Files To a Library
The Libraries tab has several publishing-related options at the top of the page that let you upload, classify, and publish files, content packs, Web links, and Google docs in Content.
1. Libraries Tab

2. Libraries Home Page

Click Contribute

Click Browse to upload a file from your computer.
Select the location where you would like to publish your content.
2.1. Save Content

If you choose you can save the content to your Personal (Private) library OR
2.2. Publish Content

If you select 'Publish to a shared library'
You can Choose the Library
You can select tags
You can provide additional information (like choosing the managed content)
Click Publish
3. Confirmation Page

View Content Brings you to the NEW Content's detail Page
Done Publishing Brings you back to the Libraries Page
Contribute Another opens another 'Upload' Screen so you can add an additional document