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