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