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