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