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