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