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