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