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