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