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