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