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)(13,14,18,19)(15,20,25,28)(16,26,24,21)(17,22,23,27)(5,6)(7,10)(8,12)(9,11)(13,15)(14,20)(16,27)(17,26)(18,25)(19,28)(21,23)(22,24) involution — undirected(1,2,3,4)(13,16)(14,21)(15,23)(17,25)(18,24)(19,26)(20,22)(27,28)(5,7,9,8)(6,10,11,12)(13,14,18,19)(15,20,25,28)(16,21,24,26)(17,27,23,22)(5,8,9,7)(6,10,11,12)(13,17)(14,22)(15,24)(16,25)(18,23)(19,27)(20,21)(26,28)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.