See the exercise Spellcheck Writing for the basic idea. Here, you use the Thesaurus function of your Word application to change tone or meaning of a line. For poetry, I progress the stanzas by using the Thesaurus function on Stanza 1 to create Stanza 2, then run Stanza 2 through Thesaurus to help generate Stanza 3, etc. so there's a progression.
Tools Required
Computer. Word-type application with Thesaurus function
Sample
Origin of Exercise
Variation on spellcheck writing (aka, beating a dying horse)