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