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