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