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