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