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)(13,14,17,23,18,22,26,28)(15,16,25,27,24,20,21,19)(5,6)(7,11)(8,10)(9,12)(13,15,18,24)(14,19,22,27)(16,23,20,28)(17,21,26,25)(2,4)(5,7,8,12)(6,9,10,11)(13,15)(14,20)(16,22)(17,25)(18,24)(19,23)(21,26)(27,28)(7,12)(9,11)(13,16,26,19,18,20,17,27)(14,21,28,24,22,25,23,15)(6,10)(9,11)(14,22)(15,24)(21,25)(23,28) 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.