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