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