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