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