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