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