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