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