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