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