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