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