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