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