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