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