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