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