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