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