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