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