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