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