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