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