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