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