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