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