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