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