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