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