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