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)(11,12,15,21,17,20,16,22)(13,18,24,34,25,33,31,38)(14,26,28,36,30,37,29,19)(23,35,27,41,39,42,40,32)(4,7)(8,10)(11,13)(12,18)(14,27)(15,24)(16,31)(17,25)(19,35)(20,33)(21,34)(22,38)(23,29)(26,41)(28,39)(30,40)(32,37)(36,42) involution — undirected(5,9)(8,10)(11,14,17,30)(12,19,20,36)(13,23,25,39)(15,29,16,28)(18,32,33,41)(21,37,22,26)(24,40,31,27)(34,42,38,35)(3,5,6,9)(4,8,7,10)(12,20)(18,33)(19,36)(21,22)(26,37)(32,41)(34,38)(35,42)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.