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