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