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