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