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