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