In the Documents tab, go to the Uploaded Documents section.  Click Upload File, then click Select File.  Select the files you want to upload then click Opensents tab, click Select Files, then select all the files you want to Upload and click Open. You can change the file name, enter a description for the document, assign it a document type then enable the visibility attributes.  Click the Upload link or click the Upload Files button at the top next to the Select Files button.