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