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