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