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