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