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