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