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