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