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