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