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