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