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