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