Where can I get the Citrix Client for OS X? Click here and and after downloading it to your Mac, click on the installer to install it.

Where can I get the Citrix Client for Windows?
If you're using Windows XP, Click here and choose Run
If you're using Windows VISTA, Click here and choose Run

(these screens assume you're running Windows XP with Service Pack 2.
If you're running a different version of Windows the screens may vary...)

You may get this window next, if so, choose Run again...

After the program copies files to your computer, you'll choose Yes...

...and then agree to the Citrix License Agreement...

...and then choose OK to complete the installation. You may need to close Internet Explorer and restart it. Then go to:
http://sam.tetonscience.org