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