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