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