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)(15,23)(16,25)(17,18)(19,21)(20,24)(22,27)(26,28)(1,2)(3,4)(5,7,9,6)(8,10,12,11)(13,15,18,24,19,25,27,26)(14,20,22,23,21,28,17,16)(5,8,9,12)(6,10,7,11)(13,16,19,23)(14,15,21,25)(17,26,22,24)(18,20,27,28)(2,4)(6,7)(10,11)(14,21)(16,23)(17,22)(20,28) involution — undirected(13,17,27,21,19,22,18,14)(15,16,26,28,25,23,24,20)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.