Running a script using keyboard shortcuts

I have a little script that copies the Mac date & time to the clipboard so I can paste it in emails & letters.

Up until now I have always kept the script in the dock & clicked it to run the script.

Can I create a keyboard shortcut to run this script? Do I do this in System Preferences > Keyboard?
I tried creating a shortcut but can’t get it to work.

There are a number of third-party apps to apply hot keys: QuicKeys, Quicksilver, iKey, FastScripts, etc.