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