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