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