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