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