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