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