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