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