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