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