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