One vertex per element, one color per generator, with an edge from x to x·s.
(1,2) involution — undirected(3,4)(5,8)(6,7)(9,10)(11,12,17,22,18,23,16,34)(13,24,28,36,29,40,27,19)(14,30,15,21,32,38,31,20)(25,37,33,42,41,35,26,39)(4,7)(8,10)(11,13,16,27,18,29,17,28)(12,19,22,24,23,36,34,40)(14,25,31,26,32,41,15,33)(20,35,30,39,21,37,38,42)(3,5,6,9)(4,8,7,10)(11,14,16,31,18,32,17,15)(12,20,22,30,23,21,34,38)(13,25,27,26,29,41,28,33)(19,35,24,39,36,37,40,42)(11,15,17,32,18,31,16,14)(12,21,22,38,23,20,34,30)(13,26,28,25,29,33,27,41)(19,35,24,39,36,37,40,42)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.