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