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