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