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