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