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