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