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