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