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