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