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