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)(11,15)(12,16)(13,14)(17,18)(19,28)(20,29)(21,26)(22,25)(23,27)(24,31)(30,32) involution — undirected(2,6)(7,8)(10,14)(11,12)(17,19,23,24)(18,20,27,32)(21,29,22,30)(25,28,26,31)(1,3,5,4)(2,7,6,8)(9,11,13,12)(10,15,14,16)(17,20)(18,24)(19,27)(21,28)(22,31)(23,32)(25,30)(26,29)(1,4,5,3)(2,8,6,7)(11,12)(15,16)(17,21,23,22)(18,25,27,26)(19,29,24,30)(20,28,32,31)(9,12,13,11)(10,16,14,15)(17,21,23,22)(18,26,27,25)(19,30,24,29)(20,28,32,31)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.