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