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