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