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