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