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