how do i download creative cloud on a second computer?

go here, sign in (if necessary) and start downloading, Adobe: Creative, marketing, and document management solutions

The same way you download it on the first one.  Install the manager, sign in, and use that to install the applications.

Creative Cloud Help / Sign out, Sign in | Creative Cloud desktop app

http://helpx.adobe.com/creative-cloud/kb/sign-in-out-creative-cloud-desktop-app.html

Creative Cloud Help / Install, update, or uninstall apps

http://helpx.adobe.com/creative-cloud/help/install-apps.html

Installing Creative Cloud Apps

http://tv.adobe.com/watch/cs6-creative-cloud-feature-tour-for-video/installing-desktop-apps-from-creative-cloud/