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