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