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