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