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