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