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