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