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