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