One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,7)(4,8)(5,6)(9,10,12,14)(11,15,16,13)(17,18)(19,25)(20,26)(21,27)(22,24)(23,28)(29,32)(30,31)(2,6)(7,8)(18,24)(19,29)(20,23)(21,30)(25,27)(31,32) involution — undirected(1,3,5,4)(2,7,6,8)(9,11,12,16)(10,13,14,15)(17,19)(18,25)(20,29)(21,23)(22,30)(24,31)(26,32)(27,28)(1,4,5,3)(2,8,6,7)(17,20)(18,26)(21,29)(22,23)(24,28)(27,32)(17,21,22,29)(18,27,24,32)(19,23,30,20)(25,28,31,26)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.