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