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