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