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