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