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