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