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