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