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