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