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