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