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