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