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