One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,9)(4,12)(5,7)(6,10)(8,14)(11,16)(13,15)(17,18)(19,23)(20,22)(21,25)(24,28)(26,30)(27,29)(31,32) involution — undirected(1,3,5,11)(2,6,7,15)(4,13,14,10)(8,16,12,9)(19,26)(20,28)(23,30)(29,31)(18,22,25,24)(23,29,30,31)(2,7)(6,15)(8,12)(9,16)(17,19,21,26)(18,23,25,30)(20,27,28,32)(22,29,24,31)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.