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