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(1,2,4,5)(3,6,7,8)(17,18,23,26)(19,20,24,22)(21,29,31,27)(25,28,32,30)(9,11,13,12)(10,14,15,16)(17,19,22,18,23,24,20,26)(21,29,30,32,31,27,28,25)(1,3,4,7)(2,6,5,8)(17,20,23,22)(18,24,26,19)(21,28,31,30)(25,29,32,27)(2,5)(6,8)(9,12,13,11)(10,14,15,16)(17,21,22,30,23,31,20,28)(18,25,24,29,26,32,19,27)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.