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