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