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