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