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