For the absolute "easiest" process using a guit-box.... you might start with "slide-guitar" (bottle-neck) and read through the newer and older threads related to the techniques.
No theory, (almost) .... JUST FUN.
http://www.mudcat.org/thread.cfm?threadid=60334#965790
Sincerely,
Gargoyle
If there ain't no pleasure - there is no need continuing.