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