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