1. Follow the directions for depositing your work, but don't click the Deposit button yet.  
  2. Click the Add More + button on the upper right hand corner and select Creative Commons license
  3. A new field will be added to your entry, somewhere towards the bottom of the page. Locate the new field and choose whether you want to license the work to the public domain (CC0) or want to choose specific Creative Commons licensing options. (If you see two CC0 entries and want to use the CC0 license, pick the first one.)
  4. Answer the questions on the kinds of licensing options you want.