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