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