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