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