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