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)(11,15)(12,14)(13,16)(19,27)(23,28)(24,32)(29,30) involution — undirected(2,6)(7,8)(11,16)(13,15)(17,18,21,26)(19,28,27,23)(20,25,22,31)(24,30,32,29)(1,3,5,4)(2,7,6,8)(9,11,12,16)(10,13,14,15)(17,19)(18,23)(20,30)(21,27)(22,29)(24,25)(26,28)(31,32)(1,3,5,4)(2,7,6,8)(10,14)(13,15)(17,19)(18,24)(20,29)(21,27)(22,30)(23,25)(26,32)(28,31)(1,4,5,3)(2,7,6,8)(17,20,21,22)(18,25,26,31)(19,29,27,30)(23,32,28,24)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.