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