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