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)(13,14,20,25)(15,21,26,22)(16,27,17,28)(18,24,19,23)(1,2,4,3)(5,6)(7,10)(8,9)(11,12)(13,15,20,26)(14,21,25,22)(16,18,17,19)(23,27,24,28)(6,9)(10,11)(13,16,19,15,20,17,18,26)(14,22,24,28,25,21,23,27)(5,7,8,12)(6,10,9,11)(13,17,19,26,20,16,18,15)(14,21,24,27,25,22,23,28)(1,3,4,2)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.