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