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