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