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