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