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