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