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