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