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