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