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)(15,20,25,28)(16,22,17,21)(23,26,24,27)(5,7,8,12)(6,9,10,11)(13,15)(14,20)(16,26)(17,27)(18,25)(19,28)(21,23)(22,24)(1,2,3,4)(13,16,18,17)(14,21,19,22)(15,23,25,24)(20,27,28,26)(6,10)(9,11)(13,14,18,19)(15,20,25,28)(16,21,17,22)(23,27,24,26)(7,12)(9,11)(13,17,18,16)(14,22,19,21)(15,24,25,23)(20,26,28,27)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.