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