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