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