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