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