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