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