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