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)(13,14,19,15)(16,20,26,22)(17,23,18,21)(24,25,28,27)(5,7,9,11)(6,10,12,8)(13,15,19,14)(16,24,26,28)(17,23,18,21)(20,25,22,27)(2,4)(5,8,9,10)(6,11,12,7)(13,16)(14,20)(15,22)(17,25)(18,27)(19,26)(21,24)(23,28)(2,4)(6,12)(7,11) involution — undirected(13,17,19,18)(14,21,15,23)(16,25,26,27)(20,24,22,28)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.