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