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