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