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