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