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