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