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