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