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