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)(15,19)(16,24)(17,22)(18,21)(20,27)(23,26)(25,28)(1,2)(3,4)(5,7,9,8)(6,10,12,11)(13,15)(14,18)(16,25)(17,21)(19,22)(20,26)(23,28)(24,27)(13,16)(14,20)(15,23)(17,26)(18,28)(19,27)(21,24)(22,25) involution — undirected(2,4)(5,7,9,8)(6,11,12,10)(14,21)(15,22)(18,19)(20,24)(23,25)(27,28)(5,8,9,7)(6,11,12,10)(14,22)(15,21)(16,26)(27,28)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.