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