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