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