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