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